Ion Implantation in Sillicides and Metals

硅化物和金属离子注入是MOS LSI的一项重要工艺技术。采用卢瑟福背散射光谱等测量了离子注入不同成分硅化钨、溅射和化学气相沉积金属的杂质浓度分布。CVD硅化钨的杂质浓度分布可以用高斯分布来描述，剖面尾化不明显。而在溅射W膜中，出现了明显的轮廓尾迹。在CVD W薄膜中可以抑制尾矿。当离子注入的WSIx进行退火时。杂质与多余的硅一起从富硅硅化物中通过硅化物的晶界迅速析出。无盖退火时杂质向外扩散迅速。研究了这些杂质谱的细节。

Ion imlantation in silicides and metals is an important process technology in MOS LSI's. Impurity concentration profiles of ion implantation in tungsten silicide with different compositions and metalS deposited by sputtering and chemical vapor diposition (CVD) were measured by Rutherford back scattering spectometry (RBS)and others.Impurity concentration profile in CVD tungsten silicide can be described by Gaussian distribution and profile tailing is not so evident. In sputtered W film, however, profile tailing occurs markedly. The tailing can be suprresed in CVD W film.when annealing of the ion implanted WSIx are performed. precipitation of the impurity ocurs rapidly together with excess Si from the Si rich silicide through the grain boundary of silicide.Out-diffusion of impurity takes place rapidly when capless annealing is done. Details of these impurity profiles are studied.