Rapid isothermal processing of strained GeSi layers

A cold-wall rapid thermal processor is used to study the oxidation and annealing properties of Ge_xSi_1-x strained layers. The dry oxidation rate of Ge_xSi_1-x is found to be the same as that of Si, while the wet oxidation rate is found to be higher than that of Si, and the oxidation rate increases with the Ge concentration (up to 20% in this study). A high fixed oxide charge density (>5 x 10¹¹/cm²) and interface trap level density (>10¹²/cm². eV) at the oxide interface have been determined from capacitance-voltage measurements. Using techniques such as X-ray rocking curve analysis, and I-V and C-V measurements of the p-n heterojunction, it is found that the degradation of electronic properties of metastable Ge_xSi₁__x strained layers during rapid thermal annealing are related to the formation of structural defects at the heterointerfaces.