Relaxed silicon-germanium (SiGe) has become an important material in the fabrication of high-quality films for various applications. Strain-relaxed SiGe buffers have been produced by at least three known methods. However, these techniques present several disadvantages, such as long growth times, thick buffer layers, rough surfaces, high residual strain degree, and high threading dislocation densities. These problems can result in low yields, increased costs, and poor quality in the devices that are grown on the buffers.
However, it has been found that a surfactant could be used to inhibit island formation in strain layer heteroepitaxy and, therefore, promote two-dimensional growth for the development of high-quality electron devices. The new technology uses antimony (Sb) as a surfactant. It has several uses in semiconductor production, including III-IV optoelectronic devices such as light-emitting diodes (LEDs) integrated on Si substrate using SiGe buffers graded to pure Ge.
This technology is available for licensing.