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1.
 应用高压原位差热方法,直接测量了压力下锗的固化参数─—固化温度与过冷度。高压差热信号表明,当压力大于3 GPa时,锗在凝固过程中可能发生结构相变。X射线结构分析表明,在最终的样品中除GeⅠ相外,还形成GeⅢ相和GeⅣ相。  相似文献   
2.
Titanium and cobalt germanides have been formed on Si (100) substrates using rapid thermal processing. Germanium was deposited by rapid thermal chemical vapor deposition prior to metal evaporation. Solid phase reactions were then performed using rapid thermal annealing in either Ar or N2 ambients. Germanide formation has been found to occur in a manner similar to the formation of corresponding silicides. The sheet resistance was found to be dependent on annealing ambient (Ar or N2) for titanium germanide formation, but not for cobalt germanide formation. The resistivities of titanium and cobalt germanides were found to be 20 μΩ-cm and 35.3μΩ-cm, corresponding to TiGe2 and Co2Ge, respectively. During solid phase reactions of Ti with Ge, we have found that the Ti6Ge5 phase forms prior to TiGe2. The TiGe2 phase was found to form approximately at 800° C. Cobalt germanide formation was found to occur at relatively low temperatures (425° C); however, the stability of the material is poor at elevated temperatures.  相似文献   
3.
The growth of GaInAsP lattice matched to GaAs using tertiary-butylphosphine and ethyldimethylindium to replace the more conventional phosphine and trimethylindium is described. The quaternary compound lattice matched to GaAs has received far less attention than related compositions that lattice match InP. Using the new sources, most of the growth problems experienced by previous workers have been avoided. Uniform compositions have been grown reproducibly without evidence of gas-phase, adduct-forming reactions. Bothn- andp-type films have been grown. Heteroepitaxy of high quality GalnAsP layers on Ge has also been achieved, and microstructural results are presented.  相似文献   
4.
This work gives an overview of the different developments for silicon germanium (Si1−xGex) from a MEMS post-processing perspective. First, the maximum processing temperature that does not introduce any damage or degradation into the standard characteristics of the CMOS driving electronics is specified. Then, the optimal type of silicon and germanium gas sources and deposition technique that results in an economical process are identified. Next, the selection criteria for a low thermal budget doping method and doping species are discussed. Finally, the advantage and disadvantage for the different approaches implemented for enhancing the physical properties of poly Si1−xGex at a CMOS backend compatible temperature are highlighted. It is shown that the optimal method depends on the application requirements and the CMOS technology used for realizing the driving electronics.  相似文献   
5.
蒲忠胜  关秋云  马军  严冬 《中国物理 C》2006,30(12):1171-1174
报道了在13.5—14.6MeV中子能区用活化法测得的76Ge(n,2n)75Ge, 70Ge(n,2n)69Ge, 70Ge(n, p)70Ga, 72Ge(n,p)72Ga, 73Ge(n,p)73Ga, 72Ge(n,α)69mZn和74Ge(n, α)71mZn的反应截面值. 中子注量用93Nb(n,2n)92mNb反应截面得到. 单能中子由T(d,n)4He反应获得. 同时还列举了已收集到的文献值以作比较.  相似文献   
6.
The results of NMR-spectroscopy studies of the structure, dynamic stereochemistry, and intermolecular interactions in solutions of organic derivatives of penta-and hexacoordinated silicon, germanium, and tin containing amidomethyl, lactamomethyl, and related bidentate ligands are surveyed. For the series of works “Dynamic stereochemistry of hypervalent compounds of silicon, germanium, and tin,” the author was awarded the Academia Europea Prize for young scientists from CIS in 1996. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 1912–1934. November, 1997.  相似文献   
7.
报道了用Co3O4 作覆盖氧化剂分析有机锗化合物中碳氢元素的方法。通过对 9个样品的十几次分析 ,碳、氢的相对误差分别小于± 1.30 % ,4 .4 0 %。方法简便 ,结果稳定可靠 ,可用于含锗有机化合物的碳氢分析。  相似文献   
8.
Assignment of all of the signals in the1H and13C NMR spectra of 1,1-dichloro-2,3,4,5-tetraphenyl-l-germacyclopenta-2,4-diene has been carried out using two-dimensional NMR spectroscopy. Translated fromIzvestiya Akademii Nauk Seriya Khimicheskaya, No. 3, pp. 623–625, March, 1997.  相似文献   
9.
有机锗(锗-132)的示差脉冲极谱研究   总被引:4,自引:0,他引:4  
用示差脉冲极谱法,在pH1.30H_2SO_4和3,4-二羟基苯甲醛(DHB)底液中,获得了有机锗(Ge-132)和无机锗Ge(Ⅳ)二个配位吸附极谱波,波峰分别为E_P2-0.62V和E_pl=-0.47V(υs.AgCI/Ag),Ge-132浓度在2.6×10_(-5)~3.1×10_(-3)mol/L范围内,Ge(Ⅳ)浓度在 3.1×10_(-5)~2.1×10_(-4)mol/L范围内分别与峰电流星线性关系.利用该示差脉冲极谱法可同时测定Ge-132和Ge(Ⅳ),用于有机锗营养口服液中Ge-132和Ge(Ⅳ)的测定结果满意.还探讨了Ge-132极谱波的性质,测定了有关动力学参数.  相似文献   
10.
Six new derivatized deltahedral Zintl ions have been synthesized by reactions between the known Zintl ions Ge(9) (n-) with the halides R(3)EX and/or the corresponding anions R(3)E(-) for E=Ge or Sn. This rational approach is based on our previous discovery that these derivatization reactions are based on nucleophilic addition to the clusters. All species were structurally characterized as their salts with potassium countercations sequestered in 2,2,2-crypt or [18]crown-6 ether. The tin-containing anions were characterized also in solutions by (119)Sn NMR spectroscopy. The reaction types for such substitutions and the structures of the new anions are discussed.  相似文献   
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