Limitations to quantitative analysis of ultra-thin SiGe quantum wells with low energy RBS

✍ Scribed by M. Draxler; S.N. Markin; P. Bauer

• Publisher: Elsevier Science
• Year: 2006
• Tongue: English
• Weight: 179 KB
• Volume: 249
• Category: Article
• ISSN: 0168-583X
• DOI: 10.1016/j.nimb.2006.03.033

✦ Synopsis

The Ge concentration in MBE-grown SiGe quantum wells can be quantitatively and non-destructively analyzed by means of low energy Rutherford backscattering (RBS), even for a 10 nm thick quantum well at a depth of about 60 nm below the surface. From the raw data quantitative information can be deduced by comparison with simulations (e.g. SIMNRA). The sensitivity of low energy RBS to changes in the Ge concentration x 1 in the quantum well and the influence of the quantum well thickness on the resulting depth resolution were investigated. The best choice of projectile conditions was found to be 500 keV He + ions because of optimized depth resolution and optimized sensitivity.