Reverse graded SiGe/Ge/Si buffers for high-composition virtual substrates

被引：75

作者：

Shah, V. A. ^{[1
]}

Dobbie, A. ^{[1
]}

Myronov, M. ^{[1
]}

Leadley, D. R. ^{[1
]}

机构：

[1] Univ Warwick, Dept Phys, Coventry CV4 7AL, W Midlands, England

来源：

JOURNAL OF APPLIED PHYSICS | 2010年 / 107卷 / 06期

基金：

英国工程与自然科学研究理事会;

关键词：

buffer layers; chemical vapour deposition; dislocation density; elemental semiconductors; germanium; Ge-Si alloys; silicon; substrates; surface roughness; THREADING-DISLOCATION DENSITIES; CHEMICAL-VAPOR-DEPOSITION; SI/SIGE HETEROSTRUCTURES; SURFACE-MORPHOLOGY; STRAIN RELAXATION; EPITAXIAL-GROWTH; SI; GE; LAYERS; GERMANIUM;

D O I：

10.1063/1.3311556

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

The effect of compositional grading rate on reverse linear graded silicon germanium virtual substrates, grown by reduced pressure chemical vapor deposition, is investigated. For a Si(001)/Ge/RLG/Si(0.22)Ge(0.78) buffer of 2.4 mu m total thickness the threading dislocation density (TDD) within the top, fully relaxed, Si(0.22)Ge(0.78) layer is 4x10(6) cm(-2), with a surface roughness of 3 nm. For a thicker buffer, where the grading rate is reduced, a lower TDD of 3x10(6) cm(-2) and a surface roughness of 2 nm can be achieved. The characteristics of reverse graded Si(0.22)Ge(0.78) virtual substrates are shown to be comparable to, or exceed, conventional buffer techniques, leading to thinner high-quality high Ge composition SiGe virtual substrates.

引用

页数：11