PLT Presentation for QD Forum

The ONLY On-Chip Quantum Dot Solution

PLT Company Overview

• Established in 2011 in

Portland OR—entirely

focused on engineering

quantum dots for on-

chip application

• World class R&D team– Total of 20 technical team

members with expertise in QD

synthesis, optical testing, LED

builds and on-chip QD testing

– 70+ patents and applications

• Outsourced manufacturing– Capital efficient

– Leverages existing manufacturing org

• Funding– Combination of venture

and strategic

• Strong engagements with industry leading companies in lighting and display

LED Market Opportunity

• LED Industry growing to ~$19B market by 2020 LED Market Penetration in solid state lighting

8% - 2015

28% - 2018

52% - 2022

Illumination

Pacific Light Technologies

Key Target Markets

TV/Display

Mobile Computing Devices

Source:LG

Source: Strategies in Light, Pennwell, 2016

Why use QDs On-chip?

>95% of white LEDs used

today are phosphor-

converted (PC) LEDs1, where

the phosphor is applied

directly to the chip

Osram

Most cost efficient, and

Most flexible form factor for

downstream integration

Osram

1. Yole, CIPS, 2015

Current on-chip solution: Phosphors

• Broad Spectrum Wasted Energy

• Difficult To Adjust Emission

• Poor overlap of Absorption w/Blue pump

• Variation Binning Losses

• Some phosphors display significant

thermal quenching and sensitivity to

environment

Phosphor Disadvantages

Narrow red

No widely

available tunable

narrow red or green

phosphor but the

technology is

steadily improving

QD Size (nm)

Bulk

Semiconductor

(Near Infrared)

Ba

nd

ga

p (

eV

)

QD Downconverters—The Ideal Phosphor

• High absorption at the blue pump wavelength

• Precise peak emission placement (± 1 nm)

• Fast excited state lifetimes—prevents saturation

• Very narrow emission spectra (25 nm FWHM

possible)

• Very high efficiencies (>90%)

• Scalable manufacturing process

Blue LED

pump

Downconverted

emission

On-chip Competitive Analysis: Phosphor vs QD

Phosphor Manufacturer FWHM

(nm)

Used for

lighting

Used for

display

Red nitride Mitsubishi 70-80 Yes Yes

PFS (red)1 Multiple (licensed

from GE)

<5 GE only Yes, by select

manufacturers

SLA (red)2 Lumileds 50 LL only No

Aluminates

(yellow/green)

Intematix 120 Yes No

Silicates

(yellow/green)

Multiple 60-70 No Yes

Ce-YAG (yellow) Multiple 120+ Yes Yes

QDs (tunable

through visible)

PLT 30-35 nm Yes Yes

1. http://pressroom.gelighting.com/

2. Nature Materials 13 (2014), 891–896

Narrow peaks have a huge efficiency impact

350 400 450 500 550 600 650 700 750 800

Wavelength (nm)

Human eyeresponse

3000K/90CRIstate of the art

3000K/90CRInarrow red

• Narrow red phosphor has a very large impact on the conversion

efficiency (CE) of a warm white LED for lighting.

• 20-30% gains in efficiency for lighting are possible by achieving a

narrow red

• 20%+ gains also possible for display but depends on gamut

0.0

0.2

0.4

0.6

0.8

1.0

1.2

400 450 500 550 600 650 700

PL

In

ten

sit

y %

Wavelength (nm)

PLT BLU - 539nm + 635nmQDs

PLT LED for BLU, pre-filterPLT LED for lighting

Emission peak placement mattersFor both Lighting and Display

Lighting: Once the red emission is narrow, CRI, R9

and lumen output are very sensitive to emission

wavelength. To utilize narrow phosphors, their

emission spectrum has to be tunable.

35nm FWHM QD 615nm 620nm 625nm PLT 620nm QD

CCT 2706 2703 2706 2777

CRI Ra 81 88 90 88.2

CRI R9 -6.6 41 79 26.2

LER (lm/Wopt) 372 357 344 351

Color Gamut

LCD

PLT

OLED

Display: Tunable

emission of QDs key to

high gamut coverage

QD challenges

Semiconductor surface and ligand shell:

- Dangling semiconductor bonds or labile ligands

- Curved surface not well defined

- Surface and ligands sensitive to O2 and H2O

- Improper treatment leads to both thermal sensitivity and oxidation

Layered

semiconductor

Semiconductor

surface

Ligand shell

Silicone

Semiconductor:

- Tunable narrow emission

- Very high absorption of blue pump

- Fast excited state lifetime

Treatment of surface significantly impacts quantum yield, thermal

sensitivity, and reliability

Phosphor Application Process

Slurry Mixture (silicone/QD or

phosphor)

Slurry applied to chip

Silicone cure ~ 150C

Measure and Bin

Send to customer

Solder onto boards

(~260C)

Assembly and Test

Operation

QDs introduced to

manufacturing flow

LED manufacturer

measures

performance level

and bins

Customer

measures

performance

Up to 50,000

hours

depending on

product

Mid-power packages

Requirements for on-chip packaging

QD materials must:

Be handled and mixed in air under a variety of ambient conditions

Be uniformly miscible with silicone (silicones chosen by LED

manufacturer, difficult to dictate)

Generate a controllable color cloud that does not decrease yield

Immediately test at the final performance level for the part

Maintain performance through multiple solder, bake and packaging steps

done by LED customer

Maintain performance from beginning of operation until end of lifetime

(spec varies, typically change must be less than 10 color points)

How does PLT solve the on-chip problem?

• Tailored for the heat and flux of on-chip

environment

• Handled in air

• Humidity Resistant

• No external environmental seal required

Built-in Protective Layers at

the QD surface

PLT QD tailored for very low self-absorption

PLT Quantum Dots

No

Overlap

0

0.5

1

400 450 500 550 600 650 700

Wavelength (nm)

Emission

Absorbance

Conventional Quantum Dots

Gap between absorption and emission

enables the high concentration required

for on-chip application and color

combinations

End result: Seamless Integration

PLT QD Materials: Simply

replaces existing phosphors

– Drop-in LED replacement in the

system

– No re-design required

– Minimum QD material (Cd)

requirements

– Works for all display sizes

– The ONLY QD solution for lighting

Drop-in replacement for Phosphor

Checklist for on-chip QDs

Absorption at 450 nm

Emission in the visible controllable to ± 1 nm

Fast excited state lifetime

High quantum efficiency at high T, high flux

Compatibility with LED packaging process

Reliability at high temperature

Reliability at high humidity

PLT On-chip QE reliability:

HTOL and WHTOL meet LED manufacturer requirements

HTOL

Results in

2014/

early 2015

PLT On-chip Color Point reliability:

HTOL and WHTOL meet LED manufacturer requirements

CIE1976 u’v’ color point degradation during

1600 hours of HTOL and 1200 hours of

WHTOL stress is well within 3 MacAdam

Ellipses

2700K

ANSI BIN

Long Term HTOL (85oC) on-chip QE reliability:

• QD’s produced in 2013

• No catastrophic failure observed in 16,000 hrs

• Exponential Fit based on measured data from 5,000 – 16,000 hrs

• L70 > 25Khrs possible

Summary

- Phosphor technology is always improving—QDs are not

the only narrow downconverter available

- Drop-in solution to the current LED packaging process is

the only one that makes sense from a downstream cost

and performance perspective

- On-chip usage of QDs is the next step for QD

downconverter technology

- PLT has met the performance and reliability requirements

of LED manufacturers using an on-chip approach

Thank You!

Questions:

Juanita.Kurtin@pacificlighttech.com

Pacific Light Technologies