中子辐照含氢硅中的与氢有关的深能级缺陷

利用深能级瞬态谱(简称DLTS),恒温下瞬态电容技术及红外吸收光谱,研究了中子辐照氢气氛中生长的n型区熔硅。相应于间隙氢的红外吸收谱带中子辐照后强度减弱。首次观察到未经退火就出现了能级为E_c=0.20eV的一个新的缺陷——Z中心,由于该中心的能级很接近于A中心,而浓度又较A中心低得多,通过改变中子剂量使费密能级处于A中心以下几个kT处,才能精确地测定Z中心的DLTS峰所在的温度。根据实验判断Z中心很可能是氢与空位的复合物,讨论了它的可能电子结构。 关键词：     

中子辐照含氢硅中的一种新EPR谱

氢气氛下生长的区熔硅(磷～10¹⁴/cm³)经镉比为10,总通量为(2.9—6.0)×10¹⁷n/cm²的中子辐照后,在77K,X波段观测到一种S=1/2的新EPR谱(标号为PK2)。g_eff值随(011)平面内磁场的角度关系呈三斜对称性。对应于缺陷在硅中一特定取向下的g张量主值及主轴相对于立方晶轴的方向余弦如下:g(±0.0004) n[100] n[010] n[001] g_{1关键词：}     

硅、锗中氧的低温红外吸收

在6—300K下,利用红外傅里叶光谱仪研究了400—4000cm^-1间的硅、锗中氧的红外吸收。采用高分辨条件时,分辨率可达0.5cm^-1。研究了在低温下利用硅的1106cm^-1吸收峰和锗的855cm^-1吸收峰探测硅和锗氧含量的探测限和误差。若样品厚度为2cm,估计在20K下,硅中氧含量探测限～9.6×10¹⁴氧原子·cm^-3,锗中氧含量探测限～3.0×10¹⁴氧原子·cm^-3。同时,对不同生长条件下直拉锗单晶的氧含量进行了研究,并与用锂沉淀法所求得的锗中氧含量加以比较。对不同氧含量的硅样品的1106cm^-1吸收峰在6—300K的变化进行了观察和讨论。 关键词：     

中子辐照含氢FZ-Si的红外吸收研究

对于中子辐照的n-FZSi(H₂),利用红外吸收光谱研究了由于辐照所产生的各种与氢有关的缺陷态。在未辐照的样品和辐照的样品中分别发现了未曾报道的1992cm^{-1和1857cm-1吸收峰。对于在n-FZSi(H₂)所引起的本征吸收峰和辐照损伤吸收峰,进行了讨论和指派。2150cm-1吸收峰则被认为是由于氢施主所引起的。 关键词：}     

草酰氯的激光诱导荧光激发谱

本文报道草酰氯C₂O₂Cl₂在358—372.5nm范围的激光诱导荧光(LIF)激发谱。对60多条振动谱带进行了归属,其中24条是吸收光谱中没有的。由振动结构得到C₂O₂Cl₂分子在X基态和?激发态的部分振动频率,其中v＂₇=84cm^-1和v＇₇=164cm^-1是新的数据。对4₀¹振动带的转动结构的分析给出转动常数A=0.190cm^-1,B=0.114cm^-1,C=0.048cm^-1。 关键词：     

原子氢、氘钝化以及质子注入掺杂硅的红外吸收

用FTIR研究了原子氢、原子氘钝化掺硼硅以及质子注入掺杂单晶硅,当原子氘钝化条件不同时分别产生了1360cm^-1和1263cm^-1的[BD]对局域振动模红外吸收带,这表明氘在单晶硅的硼受主邻近有两种可能的状态。质子注入掺杂硅的红外吸收光谱与不掺杂硅的明显不同,氢原子优先结合于硼的附近,注入氢仅约1%生成光效的缺陷,而绝大部份生成无光效的中心,它们可能是氢分子。 关键词：     

NO分子b~4Σ~-—a~4Π_i(4,0)带的吸收光谱

通过对NO与He流动混合气体放电,产生了激发态的NO(a⁴Ⅱ_ii)分子.利用光外差-浓度调制吸收光谱技术测量了NO分子在12530-12850 cm^-1波段内的吸收光谱,并标识出b⁴∑^--a⁴Ⅱ_i（4,0）带在该波段内的324条跃迁谱线.采用标准⁴∑^-—⁴Ⅱ_i哈密顿量模型,通过非线性最小二乘法拟合其中267条谱线,拟合残差(0.0071 cm^-1)接近实验系统测量误差(0.007 cm^-1).获得的主要分子常数与文献提供的常数符合,并且拟合得到了精细结构分子常数.     

用可调谐二极管激光光谱仪观测3657—3708cm-1区域CO2高分辨振转光谱

用可调谐二极管激光光谱仪观测到3657—3708cm^-1区域内CO₂各种同位素分子的9个振转谱带。首次观测到¹²C¹⁶O¹⁷O的10011—00001谱带和¹²C¹⁶O¹⁸O的11111—01101谱带,对其余7个谱带则扩充了其观测振转线的数目。用最小二乘方拟合法计算了各谱带的光谱常数,发现CO₂分子常数表中¹²C¹⁶O¹⁷O的10011—00001谱带中心v的计算值比本实验观测值大0.287cm^-1,而¹²C¹⁶O¹⁸O的11111—01101谱带中心v₀的计算值则比本实验观测值小0.048cm^-1。 关键词：     

对上庙墓地出土西周早期纺织遗痕的红外光谱和显微分析

为研究陕西省旬邑县西头遗址上庙墓地出土的西周早期铜泡和铜镜上的三处纺织遗痕P1﹑J1和J2,使用红外光谱仪﹑三维视频显微系统和扫描电子显微镜对其进行了结构分析和种类鉴别。从红外吸收光谱图中发现这三处遗痕都存在纤维素与木质素中的CH₂弯曲振动产生的1 434 cm^-1波数附近、纤维素中葡萄糖环中C—O醚键伸缩振动产生的1 080和1 033 cm^-1波数附近的强峰；在1 645～1 610 cm^-1区域内出现吸收峰，该峰代表的是木质素中共轭羰基和CC的伸缩振动；且J1﹑J2在纤维素中β-D-葡萄糖苷键的特征吸收振动谱带898 cm^-1波数附近存在强峰；这些特征峰都与天然麻类纤维的红外吸收光谱图吻合，可推测这三处纺织遗痕为麻类纺织品。显微观察发现其纤维表面较为粗糙，径向呈圆筒状或扁平的袋状，截面呈三角形和椭圆形，与麻类中的大麻显微结构相似，故推测其为大麻制品。测量其纺织密度可知，铜泡上的纺织品较为细密为23×25根·cm^-2;铜镜上的纺织品较为疏松，分别为13...     

AgI(Cr2O3)复合离子导体的光谱研究

本文研究了AgI(Cr₂O₃)复合离子导体的红外吸收光谱,近紫外、可见反射光谱。发现复合离子导体的两种谱图均与纯AgI,Cr₂O₃的不同。红外吸收光谱在882—889cm^-1处有一新吸收峰。电子谱中,AgI从430nm开始向长波方向表现的光离解特性消失。本来Cr₂O₃由配位场效应而引起的d—d吸收跃迁以410nm,530nm为中心的反射谱带,现在410nm处的谱带消失。530nm处的谱带稍有红移,且随加入Cr₂O₃量的增多而强度减弱。代之以整个紫外、可见区的较强吸收。对此,结合透射电子显微镜的分析,用双声子耦合和介质的变形极化以及配位场理论对AgI(Cr₂O₃)复合离子导体的声子谱和电子谱进行了解析。 关键词：     

The IR studies of hydrogen-defect-impurity complexes in c-Si grown in hydrogen atmosphere

Abstract

Based upon the results of studying the SiH IR bands in the float zone silicon crystal grown in hydrogen atmosphere (FZ-Si:H) some information about the H-defect-impurity complexes in the as-grown FZ-Si:H are summarized and presented.     

Positron-trap centers in neutron-irradiated silicon containing hydrogen

The defect evolution as a function of the annealing temperature has been studied in monocrystalline silicon grown in a hydrogen atmosphere and irradiated with 3.6×10¹⁷ neutrons/cm². Positron lifetime spectroscopy has been used and the results compared with infrated absorption measurements. Vacancy-H, vacancy-2H, vacancy-O–H and divacancy complexes withm hydrogen atoms (m<6) have been identified for the first time as possible positron traps.     

The Si-H IR absorption bands in NTD FZ (H2) Si and their identification

The 1832, 2054, 1980, 2066, 1970, 1984, 2016 and 2050–2150 cm^-1 Si-H infrared absorption bands in neutron transmutation doped FZ-silicon grown in a hydrogen atmosphere have been identified.     

Accelerated oxygen precipitation in fast neutron irradiated Czochralski silicon

Annealing effect of the oxygen precipitation and the induced defects have been investigated on the fast neutron irradiated Czochralski silicon （CZ-Si） by infrared absorption spectrum and the optical microscopy. It is found that the fast neutron irradiation greatly accelerates the oxygen precipitation that leads to a sharp decrease of the interstitial oxygen with the annealing time. At room temperature （RT）, the 1107cm^-1 infrared absorption band of interstitial oxygen becomes weak and broadens to low energy side. At low temperature, the infrared absorption peaks appear at 1078cm^-1, 1096cm^-1, and 1182cm^-1, related to different shapes of the oxygen precipitates. The bulk microdefects, including stacking faults, dislocations and dislocation loops, were observed by the optical microscopy. New or large stacking faults grow up when the silicon self-interstitial atoms are created and aggregate with oxygen precipitation.     

Electrical and optical properties of neutron irradiated the GeS8 glass

The GeS₈ chalcogenide glass was irradiated by four various doses of fast neutrons. An absorption band has appeared at 450 nm and developed with the neutron doses. It has been concluded that neutral defects are present in the material. From the measurements of the temperature dependence of the d.c. conductivity follows that the activation energy does not depend on the neutron dose within the measured range while the magnitude does with the peak value at neutron dose of 10¹⁷ ncm^?2.     

Hydrogen-related donor in silicon crystals grown in a hydrogen atmosphere

Neutron transmutation doped (NTD) silicon crystals grown in a hydrogen atmosphere have been investigated by infrared absorption spectroscopy at a low temperature (10 K). An effective-mass-like donor state HD^0/+ has been found at 110.8 meV below the conduction band bottom after rapid thermal annealing (RTA). The HD^0/+ formation mechanism after NTD and RTA is briefly discussed, and tentatively attributed to H atoms present in the vicinity of some residual irradiation defects, like a complex of a H atom and a H-saturated vacancy.     

Detection of C–H bonds in crystalline α-SiC by IR-absorption measurements

In SiC epilayers sp ³ C-H bond vibration bands were detected by infrared transmittance measurements. The absorption constants of the transmission peaks are related to the temperature at which the layers were grown and decrease with increasing growth temperature. The absorption centers vanish when the epilayer is removed or after annealing the sample at temperatures very much lower than the growth temperatures in a hydrogen-free atmosphere. These absorption centers are connected to hydrogen on silicon lattice sites.