1. 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

2. 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

3. 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.

4. Molecular Beam Epitaxy system for low dimensional semiconductor structures growth:QDs and QWRs etc.

5. MOCVD system for GaN based LED and LD structures growth

6. Molecular Beam Epitaxy system (V80) used for growing magnetic semiconductors

7. Class 10 clean-room for semiconductor integrated technology

8. Electron Beam Lithograph system with high resolution of 10nm (left) and The functional integration Lab of optoelectronic devices (right)

9. 2. The main research projects carried out in my group are as follows: 1.Semiconductor nano-structures and quantum devices 2. Positional growth of QDs and QWRs 3.GaAs and InP based quantum cascade materials and lasers 4.Wide band-gap semiconductor thin films and nanostructures growth 5.Organic/inorganic composite semiconductors for solar cells  Research founding supported by NSFC, 863 Hi-Tech and 973 National Major Basic Research Program etc.

10. 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 In x Ga 1-x As QDs grown on (311)B GaAs substrates. 3D images of In x Ga 1-x As / GaAs (311)B QDs (0.4  0.4  m)

11. Inserting In 0.5 Al 0.15 Ga 0.35 As strain reducing layer between QD layer & substrate d) 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 0.4 Ga 0.6 As QDs density is increased and ordering effect is improved largely.

12. 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

13. The samples of high power QD laser diodes 960nm10W QDLD optical fiber module Width of LD, 200  m Cavity length 600  m

14. The schematic structure of inclined stripe quantum-dot SLD

15. 900950100010501100 Wavelength (nm) 1400mA EL Intensity (a.u.) 400600800100012001400 0 50 100 150 200 Light Output ( 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

16. 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.

17. 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 d c InAs/InAlAs/InP QWRs b

18. Symmetry in the InAs wire alignment MBE, (001), 8ML MEE, (001), 8ML MBE, (mis-oriented), 8MLMEE, (001), 10ML

19.  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.

20. Particle population inversion based on the resonance with the optical phonon. This SL has double merits: n=3’s Bragg reflector, n=1’s electron extraction. Operation principle of quantum cascade laser

21.  The lower left fig. shows the TEM result of strain-compensated In 0.55 Ga 0.45 As/In 0.5 Al 0.5 As  The lower right fig. shows the XRD spectrum of 25 period In 0.55 Ga 0.45 As/In 0.5 Al 0.5 As QCL

22. The output power vs current for the 5.5  m strain-compensated QCL 1W QCW operation at 80K 50  C 脉冲激射

23. 80090010001100120013001400 INTENSITY(a.u.) FREQUENCY （ cm -1 ） 83K 9.1  m GaAs/AlGaAs QCL lasing spectrum 7.8  m strain-compensated QCL lasing spectrum Samples for quasi-single mode quantum cascade lasers made by our Lab. 84K 83K

24. 15 Min CSI 60 Min CSI min 60 Min CSI ZnO nanostructures grown by Stress driving Fig. （ a ）, （ b ） and （ c ）, （ d ） are FE Cross Section Imaging at growth time of 60min and 15min respectively

25. 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, 1.3  mand 1.5  m 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 (30-300  m) structures and lasers  Property studies on single QD and QWR

26. Thanks for your attention ！