Cantilever epitaxy Promising brighter LEDs

A QUARTERLY RESEARCH & DEVELOPMENT JOURNALVOLUME 6, NO. 3

FALL • 2004

Promising brighter LEDsCantilever epitaxy

What is

Sandia’s world-class science, technology,and engineering work define the Labs’ value to thenation. These capabilities must remain on thecutting edge, because the security of the U.S.depends directly upon them. Sandia’s LaboratoryDirected Research and Development ( )Program provides the flexibility to invest in long-term, high-risk, and potentially high-pay-offresearch and development that stretches the Labs’ science and technology capabilities.

supports four primary strategicbusiness objectives: nuclear weapons;nonproliferation and materials assessment; energyand infrastructure assurance; and militarytechnologies and applications; and an emergingstrategic objective in homeland security. LDRDalso promotes creative and innovative researchand development by funding projects that arediscretionary, short term, and often high risk,attracting exceptional research talent from acrossmany disciplines.

When the LDRD symbol appears in thisissue, it indicates that at some state in the historyof the technology or program, LDR fundingplayed a critical role.

On the Cover:Researcher Christine Mitchell examines a substrate used with Sandia’scantilever epitaxy growth process. This R&D 100 Award-winningprocess holds promise for brighter, light emitting diodes (LEDs) for solid-state lighting. (Photo by Randy Montoya)

Sandia Technology (ISSN: 1547-5190) is a quarterlyjournal published by Sandia National Laboratories.Sandia is a multiprogram engineering and sciencelaboratory operated by Sandia Corporation, a LockheedMartin company, for the Department of Energy. Withmain facilities in Albuquerque, New Mexico, andLivermore, California, Sandia has broad-based researchand development responsibilities for nuclearcompetitiveness and other areas of importance to theneeds of the nation. The Laboratories’ principal missionis to support national defense policies by ensuring thatthe nuclear weapon stockpile meets the highest standardsof performance. For more information on Sandia, see ourWeb site at http://www.sandia.gov

To request additional copies or to subscribe, contact:Michelle FlemingMedia Relations and Communications DepartmentMS 0165Sandia National LaboratoriesP.O. Box 5800Albuquerque, NM 87185-0165 Voice: (505) 844-4902Fax: (505) 844-1392e-mail: [email protected]

Sandia Technology Staff:Laboratory Directed Research & Development Program

Manager: Henry WestrichMedia Relations and Communications Department

Manager: Chris MillerEditor: Will KeenerTechnical Editor: Sherri MostaghniWriting: Mike Janes, Elizabeth Holm, Chris

Burroughs, Michael Padilla, and Nigel HeyPhotography: Randy J. MontoyaDesign: Alice Baltz

S A N D I A T E C H N O L O G Y

Inside CvrFrnt.qxd 11/8/04 1:12 PM Page 1

TABLE OFS A N D I A T E C H N O L O G Y

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Annealing—Microcosm inbent metal

New membrane—Microfuel cell moves closer

Reliable, deployable—Sensor architecture

Fire—Sandia–FM Globalto collaborate

R&D 100—Sandia teamswin Awards

Small business—Sandiaworking for New Mexico

Dear Readers, While the bulk of Sandia’s work

addresses national issues, ourengineers and scientists are also calledon from time to time to look at localproblems through a unique smallbusiness assistance arrangement withthe state of New Mexico. Applyingtechnologies used in national securityprograms to small business problems— often stretching or adapting them innew ways — has proven beneficial bothto the state’s economy and to Sandia.

In an article by Elizabeth Holm, aSandia researcher managing amultiple-year project to take a scientificlook at the process of metal annealing,the author makes a startlingcomparison between the crystalline cellstructure of metal and the dispersal ofgalaxies flying apart through space.

And while Independence Dayrevelers were picnicking in a Californiapark, Sandia engineers weredemonstrating a new “sensormanagement architecture” they hopewill lead to a system to allow rapidresponse of law enforcement agenciesto high-profile special events.

We also take time to brag about ourtwo R&D 100 Award winners andSandia Vice President Jim Tegnelia’sappointment as chair of the ArmyScience Board.

Another article shows how the Labscontinue to partner with private industryto address mutual problems, in thiscase high-consequence accidents andfires. Solutions to these issues havepotential benefits to not only ourcommercial partner but to the nation.

Will KeenerEditor

FROM THE

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Fall Issue 2004


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AnnealingMicrocosm in a piece of metal

In a computer simulation, a fewcrystalline cells (dark blue) grow at

the expense of their neighbors asannealing begins. When annealing isover, the substructure will be entirely

consumed. The small cells in thispicture are about one-fiftieth the

diameter of a human hair.

This article was written by ElizabethHolm, who is leading a multiyearproject to understand annealing.

Automobiles, airplanes, and cookwareall start out the same way: as flat pieces ofmetal. Engineers shape sheet metal intobumpers, wings, and pans throughsometimes complicated cycles of bendingand heating. The heating step, calledannealing, is especially important, becauseit softens the material to allow further

forming and to prevent breaking.Surprising results

followed from aSandia researchteam’s study ofbending andannealing.

Afterbending, thesubstructure ofa piece of metalorganizes intocells — tinycrystallites ofmaterialarranged likebubbles in

foam. Theresearchers knew that

cells formed as the result of acompetition. Bending tends to

smear out, or even destroy, thesubstructure. But the material’s intrinsictendency is to maintain order. In balance,the competition between bending andordering organizes the metal intocrystalline cells.

Early on, the Sandia team askedwhether other processes seek the samebalance and stumbled upon a big one, thelargest conceivable one, known as the BigBang. In the earliest moments of ouruniverse, this giant explosion sentgalaxies flying apart through space.Galaxies do not disperse randomly,

though, because their gravities attract eachother. The competition between Big Bangexpansion and gravitational orderingorganizes galaxies into cell patterns.

When we plotted metal cell structureson the same graph as galaxy spacing, wewere amazed. They followed exactly thesame curve. It is scientifically interestingand aesthetically beautiful to find amicrocosm in a bent piece of metal.

Order and chaos

While the two processes differ in theirdetails, the competition between order andchaos is the same in each. Just as bendingsmears out the substructure in metal, theBig Bang smears out the structure of theuniverse. The tendency toward crystallineorder creates a cell structure in metals;gravity does the same for galaxies. Theresult is similar structures at enormouslydifferent scales.

The multiyear project to understandthe annealing process is funded by theDepartment of Energy’s Office of BasicEnergy Sciences. Colleagues from aroundthe world, including California, the UnitedKingdom, and China, join in this effort.

Annealing is a fundamental process inmetallurgy; metalworkers have been doingit since the Bronze Age. We want tounderstand the science behind it, particul-arly how the process initiates.

Despite its long history, scientists stilldo not understand every aspect ofannealing. The Sandia team usesadvanced computer simulations to showhow the substructure of a piece of metalchanges upon heating. Because theirsimulations are so realistic, the team isable to observe and explain the criticalinitiation events for the first time.


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Expanding cells

Sandia simulations show that uponheating, certain rare cells expand at theexpense of their neighbors. These specialcells grow until they consume all theother cells, resulting in a soft material,free of substructure. Then, the bendingand heating process can start again.

This is the initiation process in anutshell. If that was all we did, we’d bethrilled. But the trip was as exciting as thedestination.

The team is now applying its resultsto annealing in aircraft aluminum andautomotive steel. More realistic annealingmodels can help industries cut costly time

and prototypes from their designschedules. Eventually, engineers may usethese models to control sheet metalforming in factories around the world.

But for now, metallurgists can enjoythe scientific connection between theirBronze Age technology and the shape ofthe Universe.

Technical contact: Elizabeth A. [email protected], (505) 844-7669

Media contact: Nigel [email protected], (505) 898-6679

A multiyearproject to

understandannealing, afundamental

metallurgyprocess dating to

the Bronze Age,has resulted in

some surprisingcomparisons of

microscopic cellstructures withthe ordering ofgalaxies in the

Universe.

This graph, referred to in the text,plots data comparing normalized

distances between galaxies (dots) and misorientations betweensubgrains in the annealing process

(squares). Part of the achieve-ment of such a plot, the author

acknowledges, is comparing two scales that are spectacularly

far apart.

New membraneMicro fuel cell moves closer


4

Sandia hasdeveloped a new

polymerelectrolyte

membrane — acritical

component forworking fuel cells

at a number ofscales.

A new type of polymer electrolytemembrane (PEM) is being developed byresearchers at Sandia NationalLaboratories to help bring the goal of amicro fuel cell closer to realization usingdiverse fuels like glucose, methanol, andhydrogen.

The new membrane, the SandiaPolymer Electrolyte Alternative (SPEA),could help fulfill the need for new,uninterrupted autonomous power sourcesfor sensors, communications, micro-electronics, healthcare applications, andtransportation.

The membrane research is one part ofa three-year Bio-Micro Fuel CellGrand Challenge program.

Recently the membrane research teamheaded by Sandia researcher ChrisCornelius demonstrated that the newS P E A could operate as high as 140d e g r e e s Celsius. It produced a peak powerof 1.1 watts per square centimeter at 2amps per square centimeter at 80 degreesCelsius.

Higher output

Under identical operating conditions,the SPEA can deliver higher poweroutputs with methanol and hydrogen thanwith Nafion, the currently recognizedstate-of-the-art PEM material for fuel cells.

Sandia researchers Cy Fujimoto (left) and Chris Cornelius hold a test micro fuel cell with the Sandia membrane. Next to Fujimoto is a micro fuel test station. (Photo by Randy Montoya)

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The SandiaPolymer

ElectrolyteAlternative couldbe used in a fuel

cell to powereverything fromsensors and cell

phones tolaptops and

automobiles.

Because SPEA can operate at elevatedtemperatures, it enables several keybenefits that Nafion cannot provide. Theseinclude smaller fuel cell stacks because ofbetter heat rejection, enhanced watermanagement, and significant resistance tocarbon monoxide poisoning. Theseperformance properties suggest that SPEAmay be a potential alternative to Nafion.

Cornelius, who developed SPEA withSandia researcher Cy Fujimoto, notes thata higher temperature PEM material is oneof the goals of the DOE’s Hydrogen, FuelCells, and Infrastructure TechnologiesProgram. A milestone is to develop apolymer electrolyte membrane forautomotive applications by 2005 thatoperates at 120 degrees Celsius for 2,000hours with low membrane interfacialresistance.

“Validation of this material as aNafion alternative would be a significantachievement — an accomplishment westrongly desire,” says Cornelius.

Critical component

A PEM is a critical component of aworking fuel cell. Its function is toconduct protons efficiently and possesslow fuel-crossover properties. It must alsobe robust enough to be assembled into afuel cell stack and have long life.

In developing SPEA the Sandia teamlooked at the success and limitations ofother PEM alternatives in order todevelop a set of characteristics for theirmodel material.

“At the beginning of this project wewere considering several polymer familiesfor a PEM alternative, including a familyof polyphenylenes,” Cornelius says.“When the physical properties of one ofthe polyphenylenes being considered as apolymer electrolyte was improved andintegrated into a working fuel cell, wehappily discovered that it worksextremely well compared to Nafion.”

Cornelius says that the SPEA he andFujimoto are developing “may be anenabling material that could have animpact on the fuel cell community andhelp Sandia become recognized as a fuelcell research organization.”

“We have already completed initialmaterial validation studies of our SPEAwith the help of our battery group and LosAlamos National Laboratory,” he says.

Next steps

The next steps, Cornelius says, are toreduce the internal resistance in the fuelcell membrane electrode assembly,optimize catalyst and ionomer com-position, improve the properties of theSPEA, and conduct life cycle testing in afuel cell environment to assess thematerial’s potential.

Understanding the material’s capa-bilities and limitations are necessary stepsin order to potentially improve thephysical properties of SPEA material andevaluate its potential value for large scalecommercialization.

“We see this SPEA material as havingthe potential of being integrated into fuelcells ranging from microwatts to kilo-watts,” he says. “Such a broad powerrange means that the Sandia PolymerElectrolyte Alternative could be used in afuel cell to power everything from sensorsand cell phones to laptops andautomobiles.”

Technical contact: Chris [email protected], (505) 844-6192

Media contact: Chris [email protected], (505) 844-0948


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Reliable, deployableD e m o n s t rating new sensor arch i t e c t u re

ow can we rapidly deploy sensors,surveillance cameras, and detectionequipment across a small geographiclocation, monitor the data they collect,and communicate amongst ourselves viamultiple command stations? That’s thequestion we’re attempting to answer,” saidSandia researcher Michael M. Johnson.

To find the answer, Johnson andcolleagues placed multiple environmentaldetectors and two high resolution videocameras at Robertson Park, Livermore,California, during Fourth of Julyfestivities this summer. They also placed amobile sensor that monitors conditionssuch as temperature and wind velocity.

While some 15,000 Livermoreresidents and visitors enjoyed barbecues,music, picnics, and other activities, Sandiaresearchers and City of Livermore PoliceDepartment members were using the

occasion to test a complex system ofsensors and other advanced tech-nology designed to keep revelers safefrom terrorist attacks.

The wireless data processingequipment was then linked to a dual-location, high-speed communicationsnetwork that allowed Sandia andpolice personnel to receive infor-mation in near real-time. The camerasprovided event security coordinatorswith a view of the stage and a remoteparking area.

No real threats were anticipated(nor experienced) at Robertson Park.Still, Sandia researchers say the testdeployment — which took about twohours — confirmed their hopes thatthe Sensor Management Architecture(SMA) system could serve animportant and valuable role forregional law enforcement ande m e rgency response.

Terrorist attacks

The idea, according to Sandiacomputer scientist Heidi Ammerlahn, is toprevent or mitigate terrorist attacks byhaving a networked, rapidly deployablesystem in place that will arm firstresponders with the information andtechnical infrastructure necessary to takeaction quickly and effectively. Anynumber of special events, both large andsmall, could benefit from such a system,she indicated.

“The benefit to local public safety isthat very specialized sensing and videomonitoring equipment can be quickly andsecurely integrated into a network, usingeither fixed wiring or encrypted wireless,to provide command staff, dispatchcenters, and field personnel with vital

Livermore (California) PoliceDepartment’s Community Outreach

Vehicle served as the commandpost for the Sensor Management

Architecture testing.

“H


information that has never been availablebefore,” said Greg Park, Livermore PoliceDepartment’s Information TechnologyCoordinator.

Larger-scale events and venues thatare attractive to terrorists are of particularconcern to the Department of HomelandSecurity — the agency funding theprogram. Depending on the detectionequipment being used, the system couldbe configured to detect any number ofweapons of mass destruction and couldalso serve as a monitoring tool for lawenforcement officials.

Hypothetical case

Ammerlahn posed a hypothetical caseof a chemical agent release at a crowdedpolitical event. With an SMA system inplace, a chem-detector could activate analarm, and identify and characterize theagent. The communications component ofthe system would immediately notifyemergency personnel and send back keyinformation. At the same time,surveillance cameras, trained on the eventlocation, would immediately zero in onthe area of interest and provide potentiallylife-saving intelligence to officials.

Officials could swiftly determine thelevel of threat, the type of agent released,the environmental conditions impactingthe release, and the whereabouts of any

suspects, she said. The information couldshave precious minutes in response time.

“Working directly with the local firstresponders, including both police and fireservices, is a new and exciting mission forour laboratory,” said Rick Stulen, a keymember of the Labs’ homeland securitymanagement team. “We are activelylooking to broaden our impact within theregion and open our doors to state andlocal entities utilizing technology beingdeveloped at the laboratory.”

First response

First responders and those responsiblefor operations plans, logistics, andemergency response efforts urgently needsystems that are reliable and easilydeployable, said Sandia’s Johnson. TheFourth of July exercise in Livermoredemonstrated how well the SMA canwork, he said.

Sandia has demonstrated similardetection and sensor architecture for SanFrancisco International Airport, and amajor East Coast city’s transportationauthority is now considering how it mightintegrate Sandia’s sensor managementarchitecture into its emergency plan.

Media contact: Mike [email protected], (925) 294-2447

The long-termgoal is to provide

a system thatcan respond

rapidly to high-profile special

events with suchimportance thatfederal agencies

such as theSecret Service

and FBI willassume

responsibility fortheir security.

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Focus on fireSandia–FM Global to collaborate


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The goal of theagreement is topursue research

and developmentto reduce the

consequences ofadverse events

such as fires.

andia has established a collaborativeresearch and development agreement(CRADA) with FM Global, one of theworld’s largest commercial and industrialproperty insurance companies(www.fmglobal.com).

The goal of the agreement is to pursueresearch and development to reduce theconsequences of adverse events such asfires. FM Global is unique as an insurerbecause its philosophy is that the majorityof all loss is preventable and as such relieson scientific research and engineering asopposed to actuarial techniques to under-write client risks. The CRADA sets thestage for additional progress in engineer-ing sciences to address high consequenceevents, says Louis Gritzo, manager forSandia’s Fire Sciences and Technologydepartment. The first task area under theagreement will focus on fire.

The two companies will use new,high-quality data from large fires todevelop and validate computer fire modelsand to develop new theories to describefire behavior. The formulation of newtheories and the development of newmodels will allow analysis of fire hazardsand predictions of fire mitigation systemperformance to be performed withconfidence, says Gritzo.

Fire-related losses

These advances are expected toprovide measurable improvements in firesafety by decreasing fire-related losses oflife and property.

“Both organizations have, or will soonhave, new fire test laboratories withdiffering, but complementary,capabilities,” says Gritzo.

New Thermal Test Complex under construction at Sandia includes offices and other facilities useful in a joint effort with FM Global. (Illustration courtesy of Dekker/Perich/Sabbatini Architects)

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FM Global andSandia have a

common interestin preventing orreducing lossesdue to fire and

other high-consequence

events. A newlysigned

agreement aimsat providing

technicaladvances for the

prevention andmitigation of

these events.

FM Global recently completedconstruction of a $78 million world-classresearch and product-testing complex. Thecompany has research laboratories thatinclude facilities for small andintermediate-scale experiments, materialflammability characterization, and open-burn rooms with calorimeter vent hoods.The largest burn laboratory, the size of anarena football field, provides a quiescentenvironment for replicating warehouse-size fires.

Open-fire facilities

Sandia currently has large open-firefacilities, small-scale laboratory facilities,and enclosed large fire facilities withcontrolled airflow to provide highlycontrolled conditions. Sandia will employexisting and new diagnostics and facilitiesincluded in the Thermal Test Complexpresently under construction.

Experiments will serve as benchmarksfor improving the knowledge of firephysics, providing validating data, anddeveloping predictive models.

Both organizations share similarobjectives, but to date have takensignificantly different approaches. BothSandia’s Fire Sciences department andFM Global are developing new instru-mentation including gauges for measuringheat transfer in very large fires. Theorganizations are also developingvalidated computer models for predictionof fire environments. Cooperation be-tween the organizations is expected tospeed-up progress to meet the needs ofboth parties.

Technical contact: Louis [email protected], (505) 844-8353

Media contact: Michael [email protected], (505) 284-5325

FM Global contact: Steven [email protected],(401) 275-3000, ext. 1945

A seven-story FLAME Test Cell is a key part of the new Thermal Test Complex, now under construction atSandia. The cell includes water-cooled walls, an airflow control system, and high-tech emission filters.

R&D 100Sandia teams win Awards


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wo Sandia National Laboratoriesresearch teams have won R&D 100Awards in the annual competitionsponsored by the Chicago-based R&DMagazine.

One award is for a new process ofgrowing gallium nitride on an etchedsapphire substrate. Called cantileverepitaxy, the process promises to makebrighter green, blue, and white lightemitting diodes (LEDS) for solid statelighting.

The other award is for the creation ofthe software framework and libraryTrilinos, which provides high-performance capabilities for solvingnumerical systems at the heart of many

complex engineering and scientificapplications.

“The research groups winning theseawards at Sandia this year are trulyinnovative and on the cutting edge ofscience,” says Sandia President C. PaulRobinson. “The cantilever epitaxy processoffers the potential for longer-lived andbetter performing LEDs. Trilinos has hada major impact on Sandia’s engineeringmodeling and simulation capabilities overthe past several years, and with its publiclicensing we are extending that to broadnational impact.”

R&D Magazine annually gives theawards to the top 100 industrialinnovations worldwide. This yearDepartment of Energy (DOE) labs won 34 R&D 100 awards, says JeannetteMallozzi, the magazine’s managing editor.

High-efficiency white light

Colored LEDs are of interest fordisplays and even higher-power lampslike traffic lights. A national initiative isnow under way to develop solid-statesources for high-efficiency white lighting.The cantilever epitaxy process of growingLEDs may help meet those needs.

“Our new process eliminates many ofthe problems that have limited the opticaland electronic performances of LEDs,previously grown on sapphire/galliumnitride substrates,” says Carol Ashby, oneof the inventors on the project.

Over the past several years, LEDshave been grown with various combi-nations of gallium nitride alloys onsapphire substrates. However, the atomsof the two materials do not line upperfectly due to differences in naturallengths of the bonds in their crystallattices. Regions of imperfections, calleddislocations, accompany this lattice

T

Sandia researcher Christine Mitchelllooks through a substrate that was

made for the new cantileverepitaxy growth process.

(Photo by Randy Montoya)


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A new Sandiaprocess for

growing galliumnitride on an

etched sapphiresubstrate and an

innovativesoftware

framework andlibrary forcomplex

engineering andscientific

applications haveboth earned R&D

100 Awards.

mismatch. The dislocations limit LEDbrightness and performance.

The new process reduces the numberof dislocations, giving the potential forlonger-lived and better performing LEDs.It also means that LEDs grown on thepatterned sapphire/gallium nitridesubstrates can produce brighter, moreefficient, green, blue, and white lightsthan previously accomplished.

David Follstaedt, another inventor onthe project, says that because of thereduction in dislocations, the processshows “great promise for making asuperior substrate for light-emittingdevices,” and has potential forapplications to a wide variety ofelectronic devices.

The cantilever epitaxy program atSandia is part of an internal, three-year$6.6 million Grand Challenge.Funding for the program also comes froma grant from the DOE Office of BuildingTechnologies for a collaborative projectwith Lumileds Lighting, a joint venturebetween Agilent Technologies and PhillipsLighting.

Trilinos

Trilinos is part of a broad effort on thepart of national laboratories, industry, andacademia to establish high-fidelitycomputational modeling and simulation asan approach to engineering and scientificunderstanding. Modeling and simulationbecome equal partners with the most basicapproaches of theory and experiment.

Trilinos provides a solution to one ofthe most difficult problems in creatingthese simulations: How can one solve themassive and complex systems ofequations required, and do so in a waythat “scales” all the way from laptopcomputers to the most powerful andcomplex parallel computers in the world?

Trilinos has become tremendouslysuccessful at addressing this “solverproblem” and has become an enabler for

the diverse simulation codes that supportalmost every engineering discipline withinthe DOE’s Advanced Simulation andComputing program.

Trilinos, led by Sandia’s MikeHeroux, is under development at both theNew Mexico and California sites, with 24researchers involved in the project.Trilinos offers what is probably the largestand most complete scalable solvercapability in the world, and it is freelyavailable to the public.

Meaning “string of pearls” in Greek,Trilinos has an architecture in whichobject-oriented packages are strungtogether like pearls on a necklace. Eachpackage provides a particular solvercapability. Trilinos began as threepackages, expanded to 20, and continuesto grow. Computational researchers andsoftware developers find Trilinosattractive because they need only focus onthose aspects of development that areunique to their package.

Trilinos offers developers a set oftools for building on multiple platforms,generating documentation, and multi-platform regression testing.

Technical contact for cantilever epitaxy: Carol [email protected], (505) 844-2303

Technical contact for Trilinos: Michael [email protected], (320) 845-7695

Media contact: Chris [email protected], (505) 844-0948

Small business assistanceSandia working for New Mexico


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ow in its third year of providingtechnical assistance to New Mexico smallbusinesses, Sandia has provided nearly300 small businesses with assistancethrough a tax credit arrangement approvedby the New Mexico Legislature.

Assistance has ranged widely in termsof technological challenges, from helpinga company make better spark plugs toaiding in the automation of the NewMexico chile industry. Researchers fromthe Labs have visited and assisted smallbusinesses throughout the state.

The Small Business Assistanceprogram allows Sandia to use a portion ofthe gross receipts taxes it pays each yearto provide technical advice and assistanceto small businesses in the state. During2003, Sandia received $1,796,000 in taxcredits. Two-thirds of the work was aimedat small businesses in rural New Mexico

and the balance went to assist smallbusinesses in Bernalillo County, where theLabs headquarters are located.

“Assistance helps small businessesmove forward through issues and helpsthem get their products or services intothe market,” said Mariann Johnston of theprogram. By mid-2004, this year’sprogram was fully allocated, with otherbusinesses on a waiting list, she said.

Driving rods

In response to a request from NewMexico officials, researchers Ted Borekand Don Susan traveled to Chama, innorthern New Mexico, to help with animportant project this spring. “Therailroad isn’t permitted to weld on trainsunless the welders know the compositionof the metals,” explained Borek. With 10

The Cumbres & Toltec narrow gaugesteam railroad remains a major

tourist attraction long after itsworking life would otherwise be

over. Sandia is helping bringhigh-tech solutions to some

turn-of-the-20th-century problems.(Photo by Randy Montoya)

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Sandia has beenworking on the

Cumbres andToltec Scenic

Railroad, runningacross the

mountains ofnorthern New

Mexico. In aunique small

businessprogram, Sandiaresearchers have

also beenworking on

projects affectingopen ranges

across the stateand the chile

fields of southernNew Mexico.

steam locomotives and only two running,railroad officials needed to move forwardwith repairs. Lacking a way to determinethe composition of several key locomotivecomponents, they asked the state for help.

Borek, of Sandia’s MaterialsCharacterization department, returnedwith drill borings from several key partsand slivers of metal removed from amassive locomotive driving rod with acold chisel. “This was a routine analysisfor us, but they were thrilled we couldhelp them out and provide a quickturnaround,” he said.

“The metallurgy was required todetermine a safe and suitable weldingprocedure for the main driving rod on thelocomotive,” explained Kim SmithFlowers, Chama resident and generalmanager of the company operating thenarrow gauge. “We had to make thatdetermination before we could approachrepairing the rod in a way that would beacceptable to the Federal RailroadAdministration.”

Don Susan returned to Chama withTed a week after the samples werecollected to test the materials forhardness. Information on the metals wassubmitted as a part of a package to therailroad administration, to get needed

welding permits and keep the repairs onschedule.

“We are always looking for principalinvestigators to work on projects likethese,” said Sandia’s Johnston. “It’s anopportunity for technical staff to workwith small businesses outside the normaleveryday projects they do and make adifference for New Mexico. In somecases, it can be technically challenging.”

Hot-iron branding

In another project, a Sandia researcherhelped a former New Mexico state brandssupervisor develop software that instantlymatches hot-iron brands with cattleowners and ranch locations. The software,expected to be commercially availablethis fall, comes at a time when thegovernment is seeking faster, moredetailed information about livestock,particularly during disease outbreaks.

Nickel Brand Software allows a userto find the owner of a brand by sketchingthe brand on the screen of a computerpalm pad with an electronic stylus or byscanning the brand with a hand scanner. Itwould allow brand states to keep a systemthat has worked well more than 100 yearsand move into the 21st century.

Software developed with the help ofSandia engineers is helping ranchers

adapt a system of brandingused for more than 100 years to the

demands of the 21st century.


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Loretta A. Martinez,founder of Moriarty-basedNickel Brand Software, saidmatching brands withranches can be tricky. InNew Mexico alone, thereare about 28,900 brandsrepresenting thousands ofworking ranches, each ofwhich may use severalbrands. (New Mexico rankssixth in the U.S. for numberof brands, after Texas,Montana, Colorado,Nebraska, and Wyoming.)

John Browning, of Sandia’s ReliabilityAssessment and Human Factorsdepartment, helped the fledgling companyby applying a reliable single-pass, three-level artificial neural network to theproblem of matching brands. This andsome human factors suggestions to helpeliminate human error moved the productforward.

The network operates similar toneurons in the brain, Browning explained.You train it to establish certain connec-tions, so that when it sees a certain input itwill fire. The system eliminates obviousbrands and arrives at a dozen or fewerchoices for a human to make, instead oflooking through a book-full ofpossibilities. “Humans are very, very goodat matching under these circumstances,”Browning said.

High-tech chile

New Mexico’s Chile Task Force, apartnership of growers, producers, andresearch institutions founded six years ago,has as a goal the improvement of NewMexico chile production andcompetitiveness.

Chris Wilson, of Sandia’s IntelligentSystems Sensors and Controls department,has been working with task force memberson a project to develop mechanicalcleaning and de-stemming for chileproducers. “The industry is moving from

manual harvesting and cleaning towardmore automated systems,” explainedWilson. “We looked at the mechanicaldevices under development and decidedwe could help most with a measuringsystem.” The system will measure redchile on a conveyor belt after mechanicalcleaning, quantifying percentages ofchiles, and “trash,” which consists ofsticks, leaves, and other natural debris.

The system can evaluate new cleaningtechnologies and may also be of use toprocessors in the future, Wilson said.Based on investigations of differentimaging technologies last year, the systemanalyzes the chile and debris on aconveyor belt based on color differences.A digital camera connected to a portablecomputer takes still images of theconveyor. Software analyzes the image andprovides feedback to the operator onpercentage of product and waste. Theoperator can then adjust the cleaner andagain check the output plots to see theeffect.

Right now, most quality measurementsare made by “eyeball,” Wilson said. Hissystem is expected to be put to the testduring this season’s harvest in October,measuring results from a new cleaningmachine developed by other members ofthe task force.

Sandia is applying technologies usedin robotics research labs in New Mexico,but “with a lot of variables” in terms ofoutdoor conditions outside of a controlledlab environment, Wilson said. “It builds onand adds to what we are doing. We arestretching ourselves in some differentdirections, but I think it will make usstronger.”

Technical contact: Mariann [email protected], (505) 284-9548


The system can evaluate new cleaningtechnologies and may also be of use to

processors in the future...

Segmenting is the process ofdetermining what is product, what isdebris, and what is background on a

conveyor belt. Picture above showsproduct in red, stems and debris ingreen, and conveyor belt in black.

Pixels can then be counted to arriveat product percentages.


im Tegnelia, vice president forDepartment of Defense Programs atSandia National Laboratories, has beenappointed chairman of the Army ScienceBoard (ASB).

The board provides the U.S. A r m ywith independent and unbiased adviceon science and technology issues that arestrategic in nature and important to larg esegments of the A r m y. “This appoint-ment has two direct benefits for Sandia,”Tegnelia says. “The first is that theboard serves in the national interest, andsecond is that it gives Sandia an oppor-tunity to be more responsive to them i l i t a r y. ”

Three other Sandiaemployees are members ofthe ASB: Executive Vi c ePresident Joan Wo o d a r d ;CFO and Vice President ofBusiness ManagementFrank Figueroa; andDirector of ManufacturingScience and Te c h n o l o g yGil Herrera.

Senior Advisors

The ASB is theDepartment of the A r m ysenior scientific advisoryb o d y. Chartered in 1977 toreplace the Army ScientificAdvisory Panel, the A S Badvises and makes recom-mendations to the secretaryof the A r m y, the chief ofs t a ff of the A r m y, theassistant secretary of theArmy (Acquisition,Logistics, and Te c h n o l o g y ) ,

the Army staff, and major A r m ycommanders on scientific and techno-logical matters of concern to the A r m y.

The board is composed ofindividuals from the private sector,academia, and non-Department ofDefense government agencies. Membersare selected according to their pre-eminence in their respective fields andappointed by the Secretary of the A r m y.


Jim Tegnelia, vice president ofDefense Programs at Sandia andchairman of Army Science Board.

Army Science BoardTegnelia named to A S B

J

PRSRT STDU.S. Postage

PAIDAlbuquerque, NMPermit NO. 232

Media Relations & Communications Dept.MS 0165Sandia National LaboratoriesP.O. Box 5800Albuquerque, NM 87185-0165

“The research groups winning these R&D 100 Awards atSandia this year are truly innovative and on the cutting

edge of science. The cantilever epitaxy process offers thepotential for longer-lived and better performing LEDs.

Trilinos has had a major impact on Sandia’s engineeringmodeling and simulation capabilities over the past severalyears, and with its public licensing we are extending that

to broad national impact.”

C. Paul RobinsonPresident and Laboratories Director

Sandia National Laboratories

SAND-2004-5014P

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How would you rate the technical level of the content?Sandia GauntletAnnealing ResearchNew Fuel Cell MembraneSensor Management ArchitectureCooperative Agreement with FM GlobalR&D 100 Award WinnersSmall Business AssistanceArmy Science Board

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Cantilever epitaxy Promising brighter LEDs

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