硅离子注入引入纳米晶对SIMOX材料进行总剂量辐射加固

本研究工作采用硅离子注入和高温退火工艺对SIMOX材料的BOX层进行总剂量辐射加固.辐射实验结果证明了该加固方法的有效性.PL谱和HRTEM图像显示了硅离子注入及退火工艺在材料的BOX层中引入了Si纳米晶,形成电子陷阱能级,有效俘获电子,从而提高了材料BOX层的抗总剂量辐射能力.     

Si离子注入对SIMOX SOI材料抗总剂量辐照性能的影响

为了提高SIMOX SOI材料抗总剂量辐照的能力,采用硅注入绝缘埋层后退火得到改性的SIMOX SOI材料.辐照前后,用pseudo-MOSFET方法测试样品的ID-VG特性曲线.结果表明,合适的硅离子注入工艺能有效提高材料抗总剂量辐照的能力.     

SOI技术的新进展

通过对最近两次SOI国际会议的分析,综述了SOI技术取得的新进展。三种SOI技术SIMOX,Smart-cut和BESOI已走向商业化,在高温与辐射环境下工作的SOI电路也走向了市场。近来人们更加重视SOI技术,是因为SOI在实现低压、低功耗电路上的突出优越性。     

Mechanism of defect formation in low-dose oxygen implanted silicon-on-insulator material

The defects and microstructure of low-dose (<0.7 × 10¹⁸ cm⁻²), oxygen-implanted silicon-on-insulator (SIMOX) material were investigated as a function of implant dose and annealing temperature by plan-view and cross-sectional transmission electron microscopy. The threading-dislocations in low-dose (0.2∼0.3×10¹⁸ cm⁻²), annealed SIMOX originate from unfaulting of long (∼10 μm), shallow (0.3 μm), extrinsic stacking faults generated during the ramping stage of annealing. As dose increases, the defect density is reduced and the structure of the buried oxide layer evolves dramatically. It was found that there is a dose window which gives a lower defect density and a continuous buried oxide with a reduced density of Si islands in the buried oxide.     

一种1MS/sCMOS/SIMOX8位A/D转换器

采用CMOS/SIMOX工艺制作1Msam ple/s 8 位A/D转换器。该A/D转换器采用半闪烁型结构,由两个4 位全并行A/D转换器实现8 位转换。电路共有31个比较器,采用斩波稳零型结构,具有结构简单和失调补偿功能。电路由2100 个器件组成,芯片面积为3.53 m m ×3.07 m m     

日趋成熟的SOI技术

SOI技术作为 2 1世纪的硅集成技术正在日益受到人们的青睐。从SOI技术的发展过程、制备工艺、开发应用及市场预测几个方面评述了SOI技术现状及前景。     

Investigation of SiGe-on-Insulator Novel Structure

SiGe-on-Insulator (SGOI) is an ideal substrate material for realizing strained-silicon structures that are very competing and popular in present silicon technology. In this paper, two methods are proposed to fabricate SGOI novel structure. One is modified Separation by Implantation of Oxygen (SIMOX) starting from pseuodomorphic SiGe thin film without graded SiGe buffer layer. Results show that two-step annealing can improve the cystallinity quality of SiGe and block the Ge diffusion in high temperature annealing. SGOI structure with good quality has been obtained through two-step annealing. The second method is proposed to achieve SGOI with high content of Ge. High quality strained relax SiGe is grown on a compliant silicon-on-insulator (SOI) substrate by UHCVD firstly. During high temperature oxidation,Ge atoms diffuse into the top Si layer of SOI. We successfully obtain SGOI with the Ge content of 38%, which is available for the growth of strained Si.     

Overview of SOI materials technology in China

In recent years, novel structure SOI materials have been fabricated successfully. Also, SiGeOI （SGOI） material, an ideal substrate for realizing strained-silicon structures, has been investigated by modified SIMOX technology. From 2002, the 100 mm, 125 mm and 150 mm SIMOX wafers have been successfully produced by Shanghai Simgui Technology Co. Ltd, a commercial spin-off of Shanghai Institute of Microsystem and Information Technology （SIMIT）, Chinese Academy of Sciences （CAS）, and shipped to the semiconductor industry worldwide. This paper presents an outlook for R ＆ D on SOI technologies, and the recent status and future prospect of SIMOX wafers in China.     

Photoreflectance Studies of SIMOX Materials

Photoreflectance (PR) was used to study SIMOX materials produced under various fabrication conditions. The position, amplitude and shape of the 3.4 eV PR response were monitored for three different sets of samples which provided information about the crystalline quality of the top silicon layer. Each sample of the first set underwent different annealing conditions. A second set of six samples was arranged such that one sample was removed at a different step of the process involving three implantation-anneal cycles. A third set of four samples was implanted with different doses of oxygen. In the first case the PR signal improved with longer annealing times and higher temperatures; in the second case the PR signal appeared to deteriorate with each cycle undergone by the samples, while in the third case the degradation of the structure increased with the increased implantation dosage. Transmission electron microscopy (TEM) was also performed in the last two cases, and its results supported the PR conclusions.     

Plasma immersion ion implantation for SOI synthesis: SIMOX and ion-cut

We have demonstrated feasibility to form silicon-on-insulator (SOI) substrates using plasma immersion ion implantation (PIII) for both separation by implantation of oxygen and ion-cut. This high throughput technique can substantially lower the high cost of SOI substrates due to the simpler implanter design as well as ease of maintenance. For separation by plasma implantation of oxygen wafers, secondary ion mass spectrometry analysis and cross-sectional transmission electron micrographs show continuous buried oxide formation under a single-crystal silicon overlayer with sharp Si/SiO₂ interfaces after oxygen plasma implantation and high-temperature (1300°C) annealing. Ion-cut SOI wafer fabrication technique is implemented for the first time using PIII. The hydrogen plasma can be optimized so that only one ion species is dominant in concentration and there are minimal effects by other residual ions on the ion-cut process. The physical mechanism of hydrogen induced silicon surface layer cleavage has been investigated. An ideal gas law model of the microcavity internal pressure combined with a two-dimensional finite element fracture mechanics model is used to approximate the fracture driving force which is sufficient to overcome the silicon fracture resistance.