A double layered porous silicon with different porosity is formed on a heavy doped p type Si(111) substrate by changing current density during the anodizing.Then a high quality epitaxial mono crystalline silicon fil...A double layered porous silicon with different porosity is formed on a heavy doped p type Si(111) substrate by changing current density during the anodizing.Then a high quality epitaxial mono crystalline silicon film is grown on the porous silicon using an ultra high vacuum electron beam evaporator.This wafer is bonded with other silicon wafer with a thermal oxide layer at room temperature.The bonded pairs are split along the porous silicon layer during subsequent thermal annealing.Thus the epitaxial Si film is transferred to the oxidized wafer to form a silicon on insulator structure.SEM,XTEM,spreading resistance probe and Hall measurement show that the SOI structure has good structural and electrical quality.展开更多
Intrinsic hydrogenated amorphous silicon(a-Si:H) film is deposited on n-type crystalline silicon(c-Si) wafer by hotwire chemical vapor deposition(HWCVD) to analyze the amorphous/crystalline heterointerface pass...Intrinsic hydrogenated amorphous silicon(a-Si:H) film is deposited on n-type crystalline silicon(c-Si) wafer by hotwire chemical vapor deposition(HWCVD) to analyze the amorphous/crystalline heterointerface passivation properties.The minority carrier lifetime of symmetric heterostructure is measured by using Sinton Consulting WCT-120 lifetime tester system,and a simple method of determining the interface state density(D_(it)) from lifetime measurement is proposed.The interface state density(D_(it)) measurement is also performed by using deep-level transient spectroscopy(DLTS) to prove the validity of the simple method.The microstructures and hydrogen bonding configurations of a-Si:H films with different hydrogen dilutions are investigated by using spectroscopic ellipsometry(SE) and Fourier transform infrared spectroscopy(FTIR) respectively.Lower values of interface state density(D_(it)) are obtained by using a-Si:H film with more uniform,compact microstructures and fewer bulk defects on crystalline silicon deposited by HWCVD.展开更多
Epitaxial monocrystalline silicon film was grown on the porous silicon using ultra high vacuum electron beam evaporation. Silicon on insulator(SOI) materials were successfully produced by bonding and etching the back ...Epitaxial monocrystalline silicon film was grown on the porous silicon using ultra high vacuum electron beam evaporation. Silicon on insulator(SOI) materials were successfully produced by bonding and etching the back of porous silicon. The quality of the SOI samples was investigated by using the cross sectional transmission electron microscopy (XTEM), spreading resistance profile (SRP), atomic force microscopy (AFM) and four crystal X ray diffraction (FCXRD). Experimental results show the SOI sample has good properties. Besides, the factors resulting in lattice strain of this SOI structure and the methods to reduce it are given.展开更多
文摘A double layered porous silicon with different porosity is formed on a heavy doped p type Si(111) substrate by changing current density during the anodizing.Then a high quality epitaxial mono crystalline silicon film is grown on the porous silicon using an ultra high vacuum electron beam evaporator.This wafer is bonded with other silicon wafer with a thermal oxide layer at room temperature.The bonded pairs are split along the porous silicon layer during subsequent thermal annealing.Thus the epitaxial Si film is transferred to the oxidized wafer to form a silicon on insulator structure.SEM,XTEM,spreading resistance probe and Hall measurement show that the SOI structure has good structural and electrical quality.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.51361022 and 61574072)the Postdoctoral Science Foundation of Jiangxi Province,China(Grant No.2015KY12)
文摘Intrinsic hydrogenated amorphous silicon(a-Si:H) film is deposited on n-type crystalline silicon(c-Si) wafer by hotwire chemical vapor deposition(HWCVD) to analyze the amorphous/crystalline heterointerface passivation properties.The minority carrier lifetime of symmetric heterostructure is measured by using Sinton Consulting WCT-120 lifetime tester system,and a simple method of determining the interface state density(D_(it)) from lifetime measurement is proposed.The interface state density(D_(it)) measurement is also performed by using deep-level transient spectroscopy(DLTS) to prove the validity of the simple method.The microstructures and hydrogen bonding configurations of a-Si:H films with different hydrogen dilutions are investigated by using spectroscopic ellipsometry(SE) and Fourier transform infrared spectroscopy(FTIR) respectively.Lower values of interface state density(D_(it)) are obtained by using a-Si:H film with more uniform,compact microstructures and fewer bulk defects on crystalline silicon deposited by HWCVD.
文摘Epitaxial monocrystalline silicon film was grown on the porous silicon using ultra high vacuum electron beam evaporation. Silicon on insulator(SOI) materials were successfully produced by bonding and etching the back of porous silicon. The quality of the SOI samples was investigated by using the cross sectional transmission electron microscopy (XTEM), spreading resistance profile (SRP), atomic force microscopy (AFM) and four crystal X ray diffraction (FCXRD). Experimental results show the SOI sample has good properties. Besides, the factors resulting in lattice strain of this SOI structure and the methods to reduce it are given.