The analysis of threading dislocation density （TDD） in Ge-on-Si layer is critical for developing lasers, light emitting diodes （LEDs）, photodetectors （PDs）, modulators, waveguides, metal oxide semiconductor fiel...The analysis of threading dislocation density （TDD） in Ge-on-Si layer is critical for developing lasers, light emitting diodes （LEDs）, photodetectors （PDs）, modulators, waveguides, metal oxide semiconductor field effect transistors （MOSFETs）, and also the integration of Si-based monolithic photonics. The TDD of Ge epitaxial layer is analyzed by etching or transmission electron microscope （TEM）. However, high-resolution x-ray diffraction （HR-XRD） rocking curve provides an optional method to analyze the TDD in Ge layer. The theory model of TDD measurement from rocking curves was first used in zinc-blende semiconductors. In this paper, this method is extended to the case of strained Ge-on-Si layers. The HR-XRD 2θ/ω scan is measured and Ge （004） single crystal rocking curve is utilized to calculate the TDD in strained Ge epitaxial layer. The rocking curve full width at half maximum （FWHM） broadening by incident beam divergence of the instrument, crystal size, and curvature of the crystal specimen is subtracted. The TDDs of samples A and B are calculated to be 1.41108 cm-2 and 6.47108 cm-2, respectively. In addition, we believe the TDDs calculated by this method to be the averaged dislocation density in the Ge epitaxial layer.展开更多
采用原位磷注入合成法在高压单晶炉内合成富磷的磷化铟 (In P)熔体 ,并利用液封直拉法 (LEC)生长出了 1 0 0 mm In P掺硫单晶材料。对富磷单晶分别用快速扫描光荧光谱技术、腐蚀金相法和扫描电镜进行了研究。结果表明在富磷量足够大的...采用原位磷注入合成法在高压单晶炉内合成富磷的磷化铟 (In P)熔体 ,并利用液封直拉法 (LEC)生长出了 1 0 0 mm In P掺硫单晶材料。对富磷单晶分别用快速扫描光荧光谱技术、腐蚀金相法和扫描电镜进行了研究。结果表明在富磷量足够大的情况下 ,晶片上会出现孔洞 ,并对孔洞周围位错的形成原因及分布进行了分析。 1 0 0 mm In P单晶的平均位错密度也没有明显的增加 ,为今后生长更大尺寸的完整 In展开更多
Macroporous silicon arrays（MSA） have attracted much attention for their potential applications in photonic crystals,silicon microchannel plates,MEMS devices and so on.In order to fabricate perfect MSA structure,phot...Macroporous silicon arrays（MSA） have attracted much attention for their potential applications in photonic crystals,silicon microchannel plates,MEMS devices and so on.In order to fabricate perfect MSA structure,photo-electrochemical （PEC） etching of MSA and the influence of etching current on the pore morphology were studied in detail.The current-voltage curve of a polished n-type silicon wafer was presented in aqueous HF using back-side illumination.The critical current density J_（PS） was discussed and the basic condition of etching current density for steady MSA growth was proposed.An indirect method was presented to measure the relation of J_（PS） at the pore tip and etching time.MSA growth was realized with the pore diameter constant by changing the etching current density according to the measuring result of J_（PS）.MSA with 295μm of depth and 98 of aspect ratio was obtained.展开更多
Infrared(IR) detectors have important applications in numerous civil and military sectors. Hg Cd Te is one of the most important materials for IR detector manufacture. This review systematically discusses the progress...Infrared(IR) detectors have important applications in numerous civil and military sectors. Hg Cd Te is one of the most important materials for IR detector manufacture. This review systematically discusses the progress of Hg Cd Te materials grown via molecular-beam epitaxy(MBE) for IR detection in terms of material physics, structure design, and fabrication. The material physics of Hg Cd Te includes crystal information, band structure, and electrical and optical properties. The characterization methods of the As-grown Hg Cd Te materials are also summarized. Then, four design structures of Hg Cd Te for IR detectors, with multilayer, superlattice, double-layer heterojunction, and barrier properties, which significantly improve the device performance,are discussed. The third section summarizes the studies on Hg Cd Te MBE-grown on different substrates, including Cd Zn Te, Si,and Ga Sb, in recent decades. This review discusses the factors influencing the growth of the Hg Cd Te film and their relationships and optimal conditions. Finally, we present the prospects and challenges associated with the fabrication and applications of Hg Cd Te materials for IR detectors.展开更多
ZnO single crystals were grown by the innovated hydrothermal method. The crystal surfaces were polished, and then studied by atom force microscope （AFM） and wet-chemical etching （WCE）. It was found that the Zn pol...ZnO single crystals were grown by the innovated hydrothermal method. The crystal surfaces were polished, and then studied by atom force microscope （AFM） and wet-chemical etching （WCE）. It was found that the Zn polar plane was smoother than O polar plane under the same polishing conditions. The etch pit density of Zn polar plane is 4.3×10^3 cm^-2, which is consistent with the previous report, while the density of etch pit of O polar plane is more than 103cm^-2. After annealing treatment, the density of etch pit of Zn plane reduces to 5.8×102 cm^2 and is superior to the current report. This investigation reveals that the high quality ZnO single crystals with fine Zn polar plane can be obtained by the innovated hydrothermal method.展开更多
基金Project supported by the Research Plan in Shaanxi Province,China(Grant No.2016GY-085)the Opening Project of Key Laboratory of Microelectronic Devices&Integrated Technology,Institute of Microelectronics,Chinese Academy of Sciences(Grant No.90109162905)+1 种基金the Fundamental Research Funds for the Central Universities(Grant No.17-H863-04-ZT-001-019-01)the National Natural Science Foundation of China(Grant Nos.61704130 and 61474085)
文摘The analysis of threading dislocation density （TDD） in Ge-on-Si layer is critical for developing lasers, light emitting diodes （LEDs）, photodetectors （PDs）, modulators, waveguides, metal oxide semiconductor field effect transistors （MOSFETs）, and also the integration of Si-based monolithic photonics. The TDD of Ge epitaxial layer is analyzed by etching or transmission electron microscope （TEM）. However, high-resolution x-ray diffraction （HR-XRD） rocking curve provides an optional method to analyze the TDD in Ge layer. The theory model of TDD measurement from rocking curves was first used in zinc-blende semiconductors. In this paper, this method is extended to the case of strained Ge-on-Si layers. The HR-XRD 2θ/ω scan is measured and Ge （004） single crystal rocking curve is utilized to calculate the TDD in strained Ge epitaxial layer. The rocking curve full width at half maximum （FWHM） broadening by incident beam divergence of the instrument, crystal size, and curvature of the crystal specimen is subtracted. The TDDs of samples A and B are calculated to be 1.41108 cm-2 and 6.47108 cm-2, respectively. In addition, we believe the TDDs calculated by this method to be the averaged dislocation density in the Ge epitaxial layer.
文摘采用原位磷注入合成法在高压单晶炉内合成富磷的磷化铟 (In P)熔体 ,并利用液封直拉法 (LEC)生长出了 1 0 0 mm In P掺硫单晶材料。对富磷单晶分别用快速扫描光荧光谱技术、腐蚀金相法和扫描电镜进行了研究。结果表明在富磷量足够大的情况下 ,晶片上会出现孔洞 ,并对孔洞周围位错的形成原因及分布进行了分析。 1 0 0 mm In P单晶的平均位错密度也没有明显的增加 ,为今后生长更大尺寸的完整 In
基金Project supported by the Specialized Research Fund for the Doctoral Program of Higher Education of China(No.200801860003).
文摘Macroporous silicon arrays（MSA） have attracted much attention for their potential applications in photonic crystals,silicon microchannel plates,MEMS devices and so on.In order to fabricate perfect MSA structure,photo-electrochemical （PEC） etching of MSA and the influence of etching current on the pore morphology were studied in detail.The current-voltage curve of a polished n-type silicon wafer was presented in aqueous HF using back-side illumination.The critical current density J_（PS） was discussed and the basic condition of etching current density for steady MSA growth was proposed.An indirect method was presented to measure the relation of J_（PS） at the pore tip and etching time.MSA growth was realized with the pore diameter constant by changing the etching current density according to the measuring result of J_（PS）.MSA with 295μm of depth and 98 of aspect ratio was obtained.
基金supported by the National Natural Science Foundation of China(Grant Nos.52072059,12274061,11774044,and 61971094)the Natural Science Foundation of Sichuan(Grant Nos.2022NSFSC0870,and2022NSFSC0485)+1 种基金the Foundation of Sichuan Excellent Young Talents(Grant No.2021JDJQ0015)the Fundamental Research Funds for the Central Universities(Grant No.ZYGX2020J023)。
文摘Infrared(IR) detectors have important applications in numerous civil and military sectors. Hg Cd Te is one of the most important materials for IR detector manufacture. This review systematically discusses the progress of Hg Cd Te materials grown via molecular-beam epitaxy(MBE) for IR detection in terms of material physics, structure design, and fabrication. The material physics of Hg Cd Te includes crystal information, band structure, and electrical and optical properties. The characterization methods of the As-grown Hg Cd Te materials are also summarized. Then, four design structures of Hg Cd Te for IR detectors, with multilayer, superlattice, double-layer heterojunction, and barrier properties, which significantly improve the device performance,are discussed. The third section summarizes the studies on Hg Cd Te MBE-grown on different substrates, including Cd Zn Te, Si,and Ga Sb, in recent decades. This review discusses the factors influencing the growth of the Hg Cd Te film and their relationships and optimal conditions. Finally, we present the prospects and challenges associated with the fabrication and applications of Hg Cd Te materials for IR detectors.
基金Supported by the Knowledge Innovation Program of the Chinese Academy of SciencesSpecial Project on Science and Technology of Fujian Province (2005HZ1023)+4 种基金Knowledge Innovation Project of the Chinese Academy of Sciences (KJCX2.YW.W01)Outstanding Youth Fund (50625205)Youth Talent of Fujian Province (2006F3140)Fujian Engineering Research Center for Optoelectronic Materials (2007K02, 2005DC105003)the National Key Project of China for Basic Research (2007CB936703)
文摘ZnO single crystals were grown by the innovated hydrothermal method. The crystal surfaces were polished, and then studied by atom force microscope （AFM） and wet-chemical etching （WCE）. It was found that the Zn polar plane was smoother than O polar plane under the same polishing conditions. The etch pit density of Zn polar plane is 4.3×10^3 cm^-2, which is consistent with the previous report, while the density of etch pit of O polar plane is more than 103cm^-2. After annealing treatment, the density of etch pit of Zn plane reduces to 5.8×102 cm^2 and is superior to the current report. This investigation reveals that the high quality ZnO single crystals with fine Zn polar plane can be obtained by the innovated hydrothermal method.
