We demonstrate an InP/InGaAs PIN photodetector with enhanced quantum efficiency by assembling silicon resonant waveguide gratings for the application of polarization sensitive systems. The measured results show that quantum efficiency of the photodetector with silicon resonant waveguide gratings can be increased by 31.6% compared with that without silicon resonant waveguide gratings at the wavelength range of 1500 to 1600 nm for TE-polarization.
National R&D activities on optical switching networkare introduced. Optical switching network testbedswere established in China including 3T-net andOBS ring and mesh network test-bed with the supportof national '863' program. As an importantmodule in OPS network, a novel all-optical serialmulticast mode is discussed.
Top-illuminated metamorphic In0.53Ga0.47As p-i-n photodetectors are grown on the ultrathin low- temperature InP buffered GaAs substrates. Photodetectors with the 300-nm-thick In0.53Ga0.47As absorption layer show a typical responsivity of 0.12 A/W to 1.55μm optical radiation, corresponding to an external quantum efficiency of 9.6%. Photodetectors with the active area of 50 × 50 （μm） exhibit the -3 dB bandwidth up to 6 GHz. These results are very encouraging for the application of this metamorphic technology to opto-electronic integrated circuit （OEIC） devices.
We investigate the thermal stresses for GaAs layers grown on V-groove patterned Si substrates by the finite-element method. The results show that the thermal stress distribution near the interface in a patterned substrate is nonuniform,which is far different from that in a planar substrate. Comparing with the planar substrate, the thermal stress is significantly reduced for the Ga As layer on the patterned substrate. The effects of the width of the V-groove, the thickness, and the width of the SiO_(2) mask on the thermal stress are studied. It is found that the SiO_(2) mask and V-groove play a crucial role in the stress of the Ga As layer on Si substrate. The results indicate that when the width of V-groove is 50 nm, the width and the thickness of the SiO_(2) mask are both 100 nm, the Ga As layer is subjected to the minimum stress. Furthermore,Comparing with the planar substrate, the average stress of the Ga As epitaxial layer in the growth window region of the patterned substrate is reduced by 90%. These findings are useful in the optimal designing of growing high-quality Ga As films on patterned Si substrates.
Ze-Yuan YangJun WangGuo-Feng WuYong-Qing HuangXiao-Min RenHai-Ming JiShuai Luo
