浸没式锗透镜加工工艺探讨

<正> 浸没式锗透镜用于红外仪器中,许多单位都加工过这种零件,其加工方法千差万别。现将我们的加工工艺简述如下。我们加工的浸没或锗透镜如图1所示:     

超声加工硅、锗小片工艺

超声加工半导体材料—硅、锗小方片和小圆片,在我国已有二十多年的历史了.由于硅、锗材料硬度高、脆性大,又是晶体结构,在加工中如果工艺不合理,就会产生尺寸不准确,崩边,缺口和碎裂等情况,所以,超声加工中的工艺研究是一项重要工作. 超声加工硅、锗小片主要由粘片、焊刀、切割、溶洗几个工序组成.如果任一道工序操作     

锗窗片的光学加工技术

加工平行平面锗窗片,采用双面研磨法修改平行度,用吸附方法粘结成盘,固着磨料抛光模粗抛,沥青抛光模精抛,解决了批量生产中等精度(平行度等于1!@)锗窗片的加工工艺。该工艺也适用于其他晶体材料的平面加工。     

关于锗单晶抛光工艺的点滴体会

锗单晶具有良好的透光性能,而且不易潮解,在红外光学仪器中,常用作光学元件.但是锗单晶质脆较软,加工时要达到比较高的光洁度和较好的平面度比较困难,需要采取一定的措施.由于我们单位科研任务的需要,自己加工了一些锗元件(主要是平行平面锗镜),进行了铭单晶的抛光工艺,现介绍如下,供同志们参考.1.表面细磨 锗单晶磨砂与光学玻璃磨砂差不多.由于锗的硬度较低,在用金钢砂细磨时,表面磨得越细越均匀越好,最后的磨料采用303#-304#.为了保证较好的平面度,最后要在玻璃平板上采用手工细磨几分钟.2.抛光 锗另件的抛光所用的辅料和抛玻璃是不大一样…     

单晶锗双面抛光工艺

<正> 单晶锗光学零件在激光和红外技术中的广泛应用,促进了晶体加工技术的发展。如何提高锗光学零件的平行度和表面光洁度已成为亟待解决的技术问题,因为平行度和光洁度的好坏直接影响着光学膜层的牢固度以及产品的使用性能,其中平行度的优劣对二氧化碳激光器输出功率的影响很大。过去对平行度要求在20″以内的高精度锗平镜的加工,确保质量的加工方法是采用光胶,而晶体零件的光胶,环境条件要求严格,工艺复杂,表面光洁度也难以保证。为此,我     

Φ256mm大口径锗透镜加工技术

随着红外技术的发展，在其光学系统中，锗材料的应用日趋地多。大口径锗材料在应力、均匀性和作为光学零件要求的精度上，对加工者都有一定难度。本文介绍了目前国内口径最大（Φ２５６ｍｍ）的多晶透镜的加工方法。从零件的特点及技术要求到加工工艺、磨具选择、抛光机理等均有叙述及分析。最后，提出进一步改进加工工艺的设想。     

硅(001)图形衬底上锗硅纳米线的定位生长

纳米线的定位生长是实现纳米线量子器件寻址和集成的前提.结合自上而下的纳米加工和自下而上的自组装技术,通过分子束外延生长方法,在具有周期性凹槽结构的硅(001)图形衬底上首先低温生长硅锗薄膜然后升温退火,实现了有序锗硅纳米线在凹槽中的定位生长,锗硅纳米线的表面晶面为(105)晶面.详细研究了退火温度、硅锗的比例及图形周期对纳米线形成与否,以及纳米线尺寸的影响.     

晶体光学零件的光胶工艺研究

以一直径为Φ20mm、平行度为10″的晶体锗窗口零件为例,介绍了晶体窗口零件加工中的关键技术。由于该零件直径小,平行差精度要求特别高,且为单晶锗材料,因此要高质高效地加工出符合技术指标的零件有相当的难度。在研究中摒弃了人们常说的晶体零件无法进行光胶的思想,大胆尝试“光胶”的方法,并结合工艺研究中经常出现的问题,有针对性地提出一套加工高精度晶体零件的控制措施。通过该措施的实施,能够很好地加工出高质高效的晶体窗口零件。实践证明：该方法适于批量加工;合格率高;能够满足设计的高精度需求。     

基于应变锗空穴双量子点的可调耦合和自旋阻塞研究

应变锗空穴量子点是实现超大规模量子计算最有前景的平台之一.由于锗空穴不受超精细相互作影响，有着较长的自旋弛豫时间和量子退相干时间，且锗中本征的强旋轨道耦合和空穴载流子的低有效质量，使得全电场操控空穴自旋量子比特得以实现，极大地降低了器件加工难度，增加了量子点的可扩展性.本文介绍了一种使用应变锗异质结制备重叠栅空穴双量子点器件的方法，完成了应变锗异质结性质测量，空穴双量子点器件制作，单量子点输运性质和双量子点输运性质研究，双量子点耦合可研究调节性研究，以及外磁场存在下的漏电流性质研究和泡利自旋阻塞解除机制的研究.这些工作为未来实现高质量自旋量子比特制备和高保真度量子逻辑门操控提供了实验平台和基本参数.     

秒级锗扫描光楔加工及检测方法

由于红外材料锗同普通光学玻璃在某些性能上存在较大差异，并且在可见光波段是不透过的，因而其在加工工艺及检测方法上同一般玻璃光学零件的加工工艺及检测方法也有所不同。我们在实践中采取一些方法是行之有效的，本文主要总结秒级扫描光模的加工工艺及检测方法。     

Pressure-induced sharp coordination change in liquid germanate

Local structures around germanium in liquid germanate have been investigated by means of in situ x-ray absorption measurements up to 9 GPa at 1273 K. Liquid germanate consisting of tetrahedrally coordinated germanium contracts with increasing pressure without significant changes in the local structure up to 2.5 GPa and then shows an abrupt fourfold-to-sixfold coordination change around 3 GPa. The coordination change is completed below 4 GPa where upon a high-density liquid consisting of octahedrally coordinated germanium becomes stable. The GeO6 octahedron in the high-density liquid is more compressible than that in solids.     

Quantitative HRTEM investigation of nanoplatelets

High resolution transmission electron microscopy experiments were performed to investigate nanoplatelets induced by ion implantation into a germanium wafer. Atomistic models were used for image simulation in order to get quantitative information from the experimental images. The geometrical phase shift analysis technique was also employed to measure the strain field induced by such defects. We discuss the limits and artefacts imposed by each approach and show how these approaches can be combined to study the atomic structure of such defects and the strain field they induce.     

Highly enhanced broadband infrared absorption of germanium by multi-layer plasmonic nano-antenna

High-sensitivity and broad bandwidth photo-detector devices are important for both fundamental studies and high-technology applications. Here, by using three-dimensional （3D） finite-difference time-domain simulation, we design an optimized 3D multi-layer gold nano-antenna to enhance the near-infrared （NIR） absorption of germanium nanoparticles. The key ingredient is the simultaneous presence of multiple plasmonic resonance modes with strong light-harvesting effect that encompass a broad bandwidth of germanium absorption band. The simulation results show more than two orders of magnitude enhanced absorption efficiency of gernanium around 1550 nm. The design opens up a promising way to build high-sensitivity and broad bandwidth NIR photo-detectors.     

Applying an improved phonon confinement model to the analysis of Raman spectra of germanium nanocrystals

The improved phonon confinement model developed previously [11] is applied for definition of germanium nanocrystal sizes from the analysis of its Raman scattering spectra. The calculations based on the model allow determining the sizes of germanium nanocrystals more precisely from the analysis of their Raman spectra. In some cases, the comparative analysis of Raman data and electron microscopy data is carried out, and good agreement is observed.     

霍尔离子源辅助制备长波红外碳化锗增透膜

为了提高锗基底的透过率和环境适应性,镀制了增透保护膜。应用电子枪蒸发加霍尔离子源辅助的方法沉积了碳化锗(Ge_1-xC_x)薄膜。通过固定霍尔离子源参数,控制沉积速率的工艺得到了不同光学常数的碳化锗薄膜。X射线衍射(XRD)测试表明,所制备的碳化锗薄膜在不同的沉积速率下均为无定形结构。采用傅立叶变换红外(FTIR)光谱仪测量了试片的透过率,使用包络法获得了相应工艺条件下的光学常数。在锗基底上双面镀制碳化锗增透膜后,长波红外7.5～11.5 μm波段的平均透过率T_ave>85%。经过环境实验之后的碳化锗膜层完好,证明碳化锗增透膜具有良好的环境适应性。     

Lattice disorder in germanium by boron ion bombardment

Abstract

The lattice disorder produced in germanium by 56keV boron-ion bombardment has been measured using the channeling-effect technique. The dependence on dose (10¹⁴-10¹⁶ ions/cm²) and implantation temperature (?90 °C to +130°C) has been studied. It is found that at room-temperature, each incident boron ion creates ?10 times more disorder in germanium than in silicon. It is remarked that, contrary to the present results, previously established anneal stages generally occur at significantly lower temperatures in germanium than in silicon.     

低温等离子体增强化学气相沉积法制备Ge反opal三维光子晶体及其光学性能

通过溶剂蒸发对流自组装法制备SiO2三维有序胶体晶体模板,采用等离子体增强化学气相沉积法在200℃低温条件下填充高折射率材料Ge,获得了Ge反opal三维光子晶体.实现了低于GeH4热分解温度的低温填充.通过扫描电镜、X射线衍射仪和傅里叶变换显微红外光谱仪对Ge反opal的形貌、成分和光学性能进行了表征.结果表明:沉积得到无定型态Ge,退火后形成多晶Ge,Ge在SiO2微球空隙内填充致密均匀.Ge反opal的反射光谱有明显的光学反射峰,表现出光子带隙效应,其带隙中心波长为1650nm和2640nm,测试的光学性能与理论计算基本符合.采用SU-8光刻胶薄膜也进行了Ge沉积,证实了SU-8模板可以耐受这一沉积温度.低温沉积降低了Ge的填充温度,可以直接采用不耐高温的高分子材料作为初始模板,单次复型制备得到多种构型的完全带隙三维光子晶体.     

Programmable Logic Based on Large Magnetoresistance of Germanium

We find extremely large low-magnetic-field magnetoresistance(~350%at 0.2T and ~180%at 0.1T) in germanium at room temperature and the magnetoresistance is highly sensitive to the surface roughness.This unique magnetoelectric property is applied to fabricate logic architecture which could perform basic Boolean logic including AND,OR,NOR and NAND.Our logic device may pave the way for a high performance microprocessor and may make the germanium family more advanced.     

单晶锗表面键合光敏染料的研究

本文在烯丙醇单体上进行了两种一甲川菁的合成,并用一种新的化学键合法将两种一甲川菁染料键合在抛光的半导体单晶锗表面。将键合有光敏染料的锗片进行了激光Raman光谱及XPS谱测试,结果表明,与对照锗片相比,键合后的锗片表面,锗衬底的一级拉曼峰强度减少,并在600～3200cm~(-1)范围内出现了与键合颜料分子相应的拉曼频移;在XPS谱中,分别进行了C,N,O,S,卤素等原子的谱图分析,证实了键合颜料后半导体单晶锗表面增加了C—N,S—C,C—O等键,结果与键合的颜料分子结构相符,表明两种光敏染料通过锗氧键共价键合于锗表面。     

Distribution of germanium in Si1 ? xGex (x < 0.1) layers grown on the Si(001) substrate as a function of layer thickness

The germanium distribution in Si(001)/Si_{1 − x} Ge _x layers as a function of the layer thickness at a low dopant concentration (x < 6%) has been investigated using high-resolution X-ray diffractometry and low-temperature photoluminescence. It has been shown that the germanium concentration increases with increasing thickness of the SiGe layer with the formation of lateral inhomogeneities at the boundary between this layer and a silicon cap layer for a layer thickness of 30 nm or more. These inhomogeneities have an oriented character and give rise to anisotropic diffuse scattering for the system of (113) and (224) asymmetric reflections from SiGe. The luminescence of these films at low temperatures and low excitation densities is an emission of localized and delocalized excitons, which is characteristic of systems with disorder. The revealed nonuniform germanium distribution in the lateral direction is associated with the accumulation of germanium in the near-surface SiGe layer and with the partial relaxation of elastic strains due to the development of surface roughness and the preferred incorporation of germanium atoms into one side of the surface ripples.