Two optical methods, namely crystal facet reflection and etching pits reflection, were used to orient and high-purity germanium crystals. The X-ray diffraction patterns of three slices that were cut from the oriented ...Two optical methods, namely crystal facet reflection and etching pits reflection, were used to orient and high-purity germanium crystals. The X-ray diffraction patterns of three slices that were cut from the oriented and crystals were measured by X-ray diffraction. The experimental errors of crystal facet reflection method and etching pits reflection method are in the range of 0.05° - 0.12°. The crystal facet reflection method and etching pits reflection method are extremely simple and cheap and their accuracies are acceptable for characterizing high purity detector-grade germanium crystals.展开更多
The high strength, radiation hardness and cost-effectiveness make Germanium the substrate of choice for high-efficiency multi-junction solar cells for space applications. Numerical modeling and large-scale simulation ...The high strength, radiation hardness and cost-effectiveness make Germanium the substrate of choice for high-efficiency multi-junction solar cells for space applications. Numerical modeling and large-scale simulation are important and indispensable tools in the analysis and development of crystal growth process. In this study, germanium single crystals with low dislocation density were produced by Czochralski method by applying the necking technique. Chemical etching pits method was used to measure the dislocation density, and a professional modeling software CrysVUn was used to obtain the thermal-stress distribution. The results show that the thermal-stress of the sample with diameter of 15 mm is nearly equal to that of other samples, so the thermal-stress does not influence the dislocation multiplication. Based on the result, the dislocation density must be strangely increased caused by gravity.展开更多
Since the early 1950’s the use of Germanium has been continuously growing as new applications are being developed. Its first commercial usage as the main material, from which the semiconductors were made, was later r...Since the early 1950’s the use of Germanium has been continuously growing as new applications are being developed. Its first commercial usage as the main material, from which the semiconductors were made, was later replaced by Silicon. The applications were then shifted to a key component in fiber optics, infrared night vision devices and space solar cells, as well as a polymerization catalyst for polyethylene terephthalate (PET). With the advance development in new technologies, the attentions have been brought back to Germanium due to its excellent semiconductor properties. New applications on the field of high efficiency solar cells, SiGe based chips, LED technologies, etc., are being developed and show a great potential. According to DERA (Deutsche Rohstoffagentur/German Mineral Resources Agency), the demand for Ge will grow considerably by 2030, pushed mostly by the increase in the fiber optics market and advanced materials sector [1]. Therefore, this paper focuses on an overview of the production chain of Germanium, especially from its concentrate up to the single crystal growth of its valuable ultra-pure metallic form to be used in high technological applications.展开更多
C<sub>2</sub>6H<sub>3</sub>1GeO<sub>5</sub>P is monoclinic,space group P2<sub>1</sub>/c,a=14.287（4）,b=8.045（2）,c=23.381（6）,β=103.79（2）°,V=2622.7,Mr=527.10,...C<sub>2</sub>6H<sub>3</sub>1GeO<sub>5</sub>P is monoclinic,space group P2<sub>1</sub>/c,a=14.287（4）,b=8.045（2）,c=23.381（6）,β=103.79（2）°,V=2622.7,Mr=527.10,Z=4,Dx=1.34g/cm3,μ=12.4cm.F（000）=1096.The final R=0.051 and R<sub>w</sub>=0.057 for 2446 observed unique reflections[I≥3σ（I）.The results indicated that all non-hydrogen atoms between phosphorus and germanium in the title compound were located almost in coplane with farthest deviation of atom Ge defined by 0. 3657.The values of Ge-C（phenyl） and Ge-C（alkyl） bond distance are 1.938（5）,1.945（5） and 1.976（5）,respectively.展开更多
利用锗单晶作为声光互作用介质 ,研制出了用于 CO2 激光器的声光开关器。主要讨论和分析了锗声光器件中出现的光吸收现象及其与温度的关系 ,尤其是换能器损耗所引起的热源。还讨论了在恒定光功率时具有不同电阻率的锗材料的吸收系数和...利用锗单晶作为声光互作用介质 ,研制出了用于 CO2 激光器的声光开关器。主要讨论和分析了锗声光器件中出现的光吸收现象及其与温度的关系 ,尤其是换能器损耗所引起的热源。还讨论了在恒定光功率时具有不同电阻率的锗材料的吸收系数和温度的关系 。展开更多
文摘Two optical methods, namely crystal facet reflection and etching pits reflection, were used to orient and high-purity germanium crystals. The X-ray diffraction patterns of three slices that were cut from the oriented and crystals were measured by X-ray diffraction. The experimental errors of crystal facet reflection method and etching pits reflection method are in the range of 0.05° - 0.12°. The crystal facet reflection method and etching pits reflection method are extremely simple and cheap and their accuracies are acceptable for characterizing high purity detector-grade germanium crystals.
文摘The high strength, radiation hardness and cost-effectiveness make Germanium the substrate of choice for high-efficiency multi-junction solar cells for space applications. Numerical modeling and large-scale simulation are important and indispensable tools in the analysis and development of crystal growth process. In this study, germanium single crystals with low dislocation density were produced by Czochralski method by applying the necking technique. Chemical etching pits method was used to measure the dislocation density, and a professional modeling software CrysVUn was used to obtain the thermal-stress distribution. The results show that the thermal-stress of the sample with diameter of 15 mm is nearly equal to that of other samples, so the thermal-stress does not influence the dislocation multiplication. Based on the result, the dislocation density must be strangely increased caused by gravity.
文摘Since the early 1950’s the use of Germanium has been continuously growing as new applications are being developed. Its first commercial usage as the main material, from which the semiconductors were made, was later replaced by Silicon. The applications were then shifted to a key component in fiber optics, infrared night vision devices and space solar cells, as well as a polymerization catalyst for polyethylene terephthalate (PET). With the advance development in new technologies, the attentions have been brought back to Germanium due to its excellent semiconductor properties. New applications on the field of high efficiency solar cells, SiGe based chips, LED technologies, etc., are being developed and show a great potential. According to DERA (Deutsche Rohstoffagentur/German Mineral Resources Agency), the demand for Ge will grow considerably by 2030, pushed mostly by the increase in the fiber optics market and advanced materials sector [1]. Therefore, this paper focuses on an overview of the production chain of Germanium, especially from its concentrate up to the single crystal growth of its valuable ultra-pure metallic form to be used in high technological applications.
文摘C<sub>2</sub>6H<sub>3</sub>1GeO<sub>5</sub>P is monoclinic,space group P2<sub>1</sub>/c,a=14.287（4）,b=8.045（2）,c=23.381（6）,β=103.79（2）°,V=2622.7,Mr=527.10,Z=4,Dx=1.34g/cm3,μ=12.4cm.F（000）=1096.The final R=0.051 and R<sub>w</sub>=0.057 for 2446 observed unique reflections[I≥3σ（I）.The results indicated that all non-hydrogen atoms between phosphorus and germanium in the title compound were located almost in coplane with farthest deviation of atom Ge defined by 0. 3657.The values of Ge-C（phenyl） and Ge-C（alkyl） bond distance are 1.938（5）,1.945（5） and 1.976（5）,respectively.
