Investigation of the subustituional behavior and the electrical activation of implanted P and N impurities in SiC

SiC 中注入 P 和 N 杂质的取代行为和电激活研究

基本信息

批准号：
13650019
负责人：
SATOH Masataka
金额：
$ 1.98万
依托单位：
Hsei University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2001
资助国家：
日本
起止时间：
2001 至 2002
项目状态：
已结题

项目摘要

1. Activation Process of the implated N impurities in 6H-SiCIn the N concentration range below 2×10^<20>/cm^3, the electrical activation is achieved by annealing at 1200℃. The substitution of the N impurities on Si sublattice sites in SiC is also promoted during the annealing at 1200℃. However, in the N concentration range above 2×10^<20>/cm^3, the number of free electrons activated from N impurities is decreased with the increase of the N concentration. In this regime, it is suggested that the excess implanted N impurities preferably occupy the interstitial sites in SiC rather than the substitutional sites.2. Activation process of the implanted P impurities in 6H-SiCThe activation process of the implanted P impurities in 6H-SiC depends on whether the implanted layer is amorphized by implantation process. In the case of the implantation with the amorphization, the implanted P impurities can occupy the Si sublatties sites while the amorphized implant layer is re-crystallized by annealing even at 1000℃, which leads immediately the electrical activation of the implanted P impurities. However, in the annealing at higher temperature induces the out-diffusion and the redistribution of the implanted P impurities in SiC. On the other hand, in the case of the implantation without the amorphization of the implanted layer using "Hot" implantation technique, the concentration of the P impurities on the Si sublattice sites is increase by increasing the annealing temperature, which results in the increase of the free electron concentration in SiC. However, the obtained free electron concentration of the "Hot" implanted SiC is lower than the case of the amorphized implant layer. It is suggested that a part of the implanted P impurities occupy the interstitial sites in SiC.

1. 6H-SiC中嵌入N杂质的激活过程在N浓度低于2×10^<20>/cm^3的范围内，通过1200℃退火实现Si亚晶格上N杂质的取代。在1200℃退火过程中，SiC中的位点也得到促进，但是，在N浓度高于2×10^<20>/cm^3的范围内，随着N浓度的增加，N杂质激活的自由电子数量减少，表明过量注入的N杂质优先占据SiC中的间隙位点，而不是取代位点。2． 6H-SiC中注入的P杂质6H-SiC中注入的P杂质的激活过程取决于注入过程中注入层是否非晶化。随着非晶化，注入的P杂质可以占据Si亚晶格位点，而非晶化的注入层即使在1000℃下退火也会重新结晶，这导致注入的P杂质立即电激活，但是在更高温度的退火中。另一方面，在没有非晶化的情况下，引起SiC中注入的P杂质的向外扩散和重新分布。在采用“热”注入技术的注入层中，通过提高退火温度，Si亚晶格位点上的P杂质浓度增加，导致SiC中的自由电子浓度增加，但获得的自由电子浓度为“热”注入的SiC低于非晶注入层的情况，这表明部分注入的P杂质占据了SiC中的间隙位置。