Real-time stress evolution during Si1-xGex heteroepitaxy: Dislocations, islanding, and segregation

被引：117

作者：

Floro, JA ^{[1
]}

Chason, E ^{[1
]}

Lee, SR ^{[1
]}

Twesten, RD ^{[1
]}

Hwang, RQ ^{[1
]}

Freund, LB ^{[1
]}

机构：

[1] BROWN UNIV,DIV ENGN,PROVIDENCE,RI 02912

来源：

JOURNAL OF ELECTRONIC MATERIALS | 1997年 / 26卷 / 09期

关键词：

heteroepitaxy; islanding; roughening; SiGe; strain relaxation; surface segregation;

D O I：

10.1007/s11664-997-0233-2

中图分类号：

TM [电工技术]; TN [电子技术、通信技术];

学科分类号：

0808 ; 0809 ;

摘要：

We have used sensitive real-time measurements of film stress during Si1-xGex molecular beam epitaxy to examine strain relaxation due to coherent island formation, and to probe the kinetics of Ge surface segregation. We first describe our novel curvature-measurement technique for real-time stress determination. Measurements of the relaxation kinetics during high temperature Si79Ge21 growth on Si (001) are reported in which formation of highly regular arrays of [501]-faceted islands produce 20% stress relaxation. An island shape transition is also observed that reduces the effective stress by up to 50% without dislocations. Nonuniform composition profiles due to Ge surface segregation during growth of planar alloy films are determined with submonolayer thickness resolution from the real-time stress evolution. Up to two monolayers of Ge can segregate to the growth surface.

引用

页码：969 / 979

页数：11