Mechanism of cleaning Si(100) surface using Sr or SrO for the growth of crystalline SrTiO3 films
Mechanism of cleaning Si(100) surface using Sr or SrO for the growth of crystalline SrTiO3 films
复制标题
使用 Sr 或 SrO 清洁 Si(100) 表面以生长晶体 SrTiO3 薄膜的机制
DOI：
10.1116/1.1491547
复制
发表时间：
2002
影响因子：
1.4
通讯作者：
W. Ooms
中科院分区：
文献类型：
--
作者：
Yi Wei;Xiaoming Hu;Yong Liang;D. C. Jordan;B. Craigo;R. Droopad;Z. Yu;A. Demkov;J. Edwards;W. Ooms
已经开发了一种使用Sr或SrO去除SiO2并产生有序Si（100）表面的方法。在该技术中，在真空分子束外延系统中，在接收态Si（100）晶片上沉积几个Sr或SrO单层。然后将衬底加热至800 °C约5分钟，去除SiO2以留下Sr或SrO封端的有序Si（100）表面。 这种Sr或SrO封端的Si（100）表面非常适合于晶体高k电介质SrTiO 3膜的生长。采用程序升温脱附法研究了Sr和SrO对Si（100）表面SiO2的脱附机理。在温度循环过程中，我们观察到的物种主要是SiO和O，没有观察到显著量的含Sr物种。我们认为SiO2的去除是由于催化反应SiO2+Sr（或SrO）→SiO（g）+O+Sr（或SrO）。SiO2/Si界面上的SiO2+Si→2SiO（g）反应受到限制，抑制了点蚀的形成。Sr或SrO在氧化物去除过程中的主要作用是催化剂，促进SiO的形成，钝化新暴露的Si表面，防止进一步的刻蚀和在衬底中形成凹坑。在该技术中，在真空分子束外延系统中，在接收态Si（100）晶片上沉积几个Sr或SrO单层。然后将衬底加热至800 °C约5分钟，去除SiO2以留下Sr或SrO封端的有序Si（100）表面。 这种Sr或SrO封端的Si（100）表面非常适合于晶体高k电介质SrTiO 3膜的生长。采用程序升温脱附法研究了Sr或SrO对Si（100）表面SiO2的脱附机理。在温度循环过程中，我们观察到的物种主要是SiO和O，没有观察到显著量的含Sr物种。我们认为SiO2的去除是由于催化反应SiO2+Sr（或SrO）→SiO（g）+O+Sr（或SrO）。抑制了SiO2/Si界面的SiO2+Si→2SiO（g）反应，抑制了孔的形成。
A method for removing SiO2 and producing an ordered Si(100) surface using Sr or SrO has been developed. In this technique, a few monolayers of Sr or SrO are deposited onto the as-received Si(100) wafer in an ultrahigh vacuum molecular-beam epitaxy system. The substrate is then heated to ∼800 °C for about 5 min, the SiO2 is removed to leave behind a Sr- or SrO-terminated ordered Si(100) surface. This Sr- or SrO-terminated Si(100) surface is well suited for the growth of crystalline high-k dielectric SrTiO3 films. Temperature programmed desorption measurements were carried out to understand the mechanism of removing SiO2 from Si(100) using Sr or SrO. The species we observed coming off the surface during the temperature cycle were mainly SiO and O, no significant amount of Sr containing species was observed. We conclude that the SiO2 removal is due to the catalytic reaction SiO2+Sr(or SrO)→SiO(g)+O+Sr(or SrO). The reaction SiO2+Si→2SiO(g) at the SiO2/Si interface is limited and the pit formation is suppressed. The main roles that Sr or SrO play during the oxide removal process are catalysts promoting SiO formation and passivating the newly exposed Si surface, preventing further etching and the formation of pits in the substrate.A method for removing SiO2 and producing an ordered Si(100) surface using Sr or SrO has been developed. In this technique, a few monolayers of Sr or SrO are deposited onto the as-received Si(100) wafer in an ultrahigh vacuum molecular-beam epitaxy system. The substrate is then heated to ∼800 °C for about 5 min, the SiO2 is removed to leave behind a Sr- or SrO-terminated ordered Si(100) surface. This Sr- or SrO-terminated Si(100) surface is well suited for the growth of crystalline high-k dielectric SrTiO3 films. Temperature programmed desorption measurements were carried out to understand the mechanism of removing SiO2 from Si(100) using Sr or SrO. The species we observed coming off the surface during the temperature cycle were mainly SiO and O, no significant amount of Sr containing species was observed. We conclude that the SiO2 removal is due to the catalytic reaction SiO2+Sr(or SrO)→SiO(g)+O+Sr(or SrO). The reaction SiO2+Si→2SiO(g) at the SiO2/Si interface is limited and the pit formation is suppresse...