The surface morphology of GaN grown by MOCVD on GaN/Si template was studied.Rough morphology and deep pinhole defects on some surface areas of the samples were observed and studied.The formation of rough morphology is...The surface morphology of GaN grown by MOCVD on GaN/Si template was studied.Rough morphology and deep pinhole defects on some surface areas of the samples were observed and studied.The formation of rough morphology is possibly related to Ga-Si alloy produced due to poor thermal stability of template at high temperature.The deep pinhole defects generated are deep down to the surface of MBE-grown GaN/Si template.The stress originated from the large thermal expansion coefficient difference between GaN and Si may be related to the formation of the pinhole defects.The surface morphology of the GaN can be improved by optimizing the GaN/Si template and decreasing the growth temperature.展开更多
Single and multiple quantum wells of lattice-matched superlattices material GaAs/A1xGal-xAs have been studied as photoelectrodes in photoelectrochemical cells containing nonaqueous electrolyte.Structured photocurrent ...Single and multiple quantum wells of lattice-matched superlattices material GaAs/A1xGal-xAs have been studied as photoelectrodes in photoelectrochemical cells containing nonaqueous electrolyte.Structured photocurrent spectra in the potential range of-1.8 to 1.0 V(vs standard calomel electrode)were obtained.The quantum yields for both superlattice electrodes were estimated and compared.展开更多
基金Project supported by Special Funds for Major State Basic Research Project(G2000683 and 2002CB311903)Nationel Natural Foundation of China(60136020)Key Imnovation Program of Chinese Academy of Science and National High Technology R&D Pogram of China(2002AA305304)
文摘The surface morphology of GaN grown by MOCVD on GaN/Si template was studied.Rough morphology and deep pinhole defects on some surface areas of the samples were observed and studied.The formation of rough morphology is possibly related to Ga-Si alloy produced due to poor thermal stability of template at high temperature.The deep pinhole defects generated are deep down to the surface of MBE-grown GaN/Si template.The stress originated from the large thermal expansion coefficient difference between GaN and Si may be related to the formation of the pinhole defects.The surface morphology of the GaN can be improved by optimizing the GaN/Si template and decreasing the growth temperature.
基金the National Natural Science Foundation of China。
文摘Single and multiple quantum wells of lattice-matched superlattices material GaAs/A1xGal-xAs have been studied as photoelectrodes in photoelectrochemical cells containing nonaqueous electrolyte.Structured photocurrent spectra in the potential range of-1.8 to 1.0 V(vs standard calomel electrode)were obtained.The quantum yields for both superlattice electrodes were estimated and compared.
