Report for China Frontier Workshop (June 22nd 2006 Beijing) Wang Zhanguo
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Transcript of Report for China Frontier Workshop (June 22nd 2006 Beijing) Wang Zhanguo
Report for China Frontier Workshop(June 22nd 2006 Beijing)
Wang Zhanguo
Key Lab. of Semiconductor Materials Science, Institute of Semiconductors, Chinese Academy of Sciences,
P. O. Box 912, Beijing 100083,P.R.China
Outline 1. A Brief introduction of the IS,CAS
2. Main research projects and achievement in our Lab
4. Topics interesting for international collaboration
1. A Brief introduction of the Institute of Semiconductors, Chinese Academy of Sciences
The Institute originally was a division of the Institute of Physics, CAS, and it was independent on the 16th September 1960.
Through the period of more than 45 years, the Institute has now grown up a multidisciplinary research institution and research areas includes semiconductor physics, materials, devices and their applications.
It has two national research centers, three state key labs, one key lab of CAS , 10 joint venture enterprises, Library and Information Center etc.
Main Research Building
Compound Crystal Technology Co., Ltd can supply LEC,VGF and HB GaAs with 2-6 inches and 2-3 inches InP Epi-ready wafers.
The Integrated Technology Center
There are now 452 staffs in the Institute, 270 are academic staffs including 71 full professors and 62 associate professors. There are seven Members of the CAS and two Members of the CAE.
The institute has 408 postgraduate students, 18 postdoctoral researchers, 233 PhD and 157 MSc students, respectively.
Molecular Beam Epitaxy system for low dimensional semiconductor structures
growth:QDs and QWRs etc.
MOCVD system for GaN based LED and LD structures growth
Molecular Beam Epitaxy system (V80) used for growing magnetic semiconductors
Class 10 clean-room for semiconductor integrated technology
Electron Beam Lithograph system with high resolution of 10nm (left) and The
functional integration Lab of optoelectronic devices (right)
2. The main research projects carried out in my group are as follows:
1.1. Semiconductor nano-structures and quantum devSemiconductor nano-structures and quantum devicesices
2. Positional growth of QDs and QWRs2. Positional growth of QDs and QWRs3.3. GaAs and InP based quantum cascade materials GaAs and InP based quantum cascade materials
and lasersand lasers4.4. Wide band-gap semiconductor thin films and nanWide band-gap semiconductor thin films and nan
ostructures growthostructures growth5.5. Organic/inorganic composite semiconductors for Organic/inorganic composite semiconductors for
solar cells solar cells
Research founding supported by NSFC, 863 Hi-Tech and 973 National Major Basic Research Program etc.
Changing In composition x of InGaAs QDs
x=0.3 x=0.4 x=0.5
Lift 1 and 2 are the 2D AFM images of InxGa1-xAs QDs grown on (311)B GaAs substrates.
3D images of InxGa1-xAs / GaAs (311)B QDs (0.4 0.4m)
Inserting In0.5Al0.15Ga0.35As strain reducing layer between QD layer & substrate
d)
b a
c
(a), (b) and (c), (d) are without and with the buried layer respectively.
Comparing fig.a,b and c,d, the In
0.4Ga0.6As QDs de
nsity is increased and ordering effect is improved largely.
Characteristics of high power In(Ga)As/GaAs QDLD
Light output power from the uncoated facets vs the current
EL spectra of a QD laser below and above the threshold current
The samples of high power QD laser diodes
960nm10W QDLD optical fiber module
Width of LD, 200m
Cavity length 600m
0 1000 2000 3000 4000 5000 60000.0
0.5
1.0
1.5
100m apertureuncoated surface
power from both facets
Po
wer
(W
)
Time (hour)
The schematic structure of inclined stripe quantum-dot SLD
P -m eta l
S iO 2
1 m P -A l G a A s 0 .5 0 .5
m A l G a A s (y= 0 -0 .5 )y 1 -y
Q u an tu m d o ts ac tiv e reg io n
0 .2 m A l G a A s (y= 0 .5 -0 ) y 1 -y
1 m n -A l G a A s 0 .5 0 .5
(1 00 ) n G aA s S u bstra te+
0 .5 m n G aA s b u ffe r +
m p G aA s+
6 O
900 950 1000 1050 1100
Wavelength (nm)
1400mA
EL
Inte
nsi
ty
(a.u
.)
400 600 800 1000 1200 1400
0
50
100
150
200
Lig
ht
Ou
tpu
t (
m W
)
Injection Current (mA)
Light output power of the QD-SLD under CW operation at RT.
Output spectrum of QD-SLD under 1400mA CW pumping current at RT.
The Characteristics of quantum dot-SLD: CW output power 200mW, the spectral bandwidth 60nm at RT
10nm ( 110 )
( 1-10 )
The diagonally aligned self-assembled InAs/InAlAs/InP(100) QWR arrays
The cross-sectional TEM images and PL spectra of 5 periods 6.5 ML InAs / 10 nm InAlAs QWR arrays.
The alignment of the QWRs grown on InP substrates with different buffer layers
InAs/[(InAlAs)2/(InGaAs)2]
InAs/InGaAs/InP QWRs
InAs/[(InAlAs)4/(InGaAs)2]
30nm
a
dc
InAs/InAlAs/InP QWRsb
Symmetry in the InAs wire alignment
MBE, (001), 8ML MEE, (001), 8ML
MBE, (mis-oriented), 8ML MEE, (001), 10ML
Lower Left fig. shows InAs QWRs grown on the (110) cleavage surface of GaAs/AlGaAs SLs
Lower right fig. demonstrates the InAs QDs grown in the patterned GaAs substrates.
)(24.1 23 EE
Particle population inversion based on the resonance with the optical phonon.
meVEE 3512
This SL has double merits: n=3’s Bragg reflector,n=1’s electron extraction.
Operation principle of quantum cascade laser
The lower left fig. shows the TEM result of strain-compensated In0.55Ga0.45As/In0.5Al0.5As
The lower right fig. shows the XRD spectrum of 25 period In0.55Ga0.45As/In0.5Al0.5As QCL
29 30 31 32 33 34 35
100
101
102
103
104
105
106
Inte
nsi
ty (
a.u
.)
Theta
G069
The output power vs current for the 5.5m strain-compensated QCL
0 1 2 3 4 5 6 7
0.0
0.5
1.0
Po
we
r (W
)
Current (A)
1W QCW operation at 80K
4 6 8 10
50C 脉冲激射
800 900 1000 1100 1200 1300 1400
INT
EN
SIT
Y(a
.u.)
FREQUENCY ( cm-1 )
83K 9.1m GaAs/AlGaAs QCL lasing spectrum
2 4 6 8 10 12 14 16
0
1x103
2x103
3x103
Inte
nsity
(a.u
.)Wave length (m)
7.8m strain-compensated QCL lasing spectrum
Samples for quasi-single mode quantum cascade lasers made by our Lab.
84K83K
15 Min CSI 15 Min CSI
60 Min CSImin 60 Min CSI
ZnO nanostructures grown by Stress drivingFig. ( a ) , ( b ) and ( c ) , ( d ) are FE Cross Section Imaging at growth time of 60min and 15min respectively
3. Topics interesting for international collaboration Positional growth of semiconductor QDs and QWRs
Quantum dot devices for systems applications
such as: high power QD Laser, 1.3mand 1.5m QD
lasers, super- luminescence diodes for optical fiber
communication; QD inferred detectors; QD single
photon source for quantum computation etc.
Band energy engineering design for THz (30-300m)
structures and lasers
Property studies on single QD and QWR
Thanks for your attention!