ABSTRACT
The field of silicon (Si)-based heterostructures solidly rests on the shoulders of materials scientists and crystal growers, those purveyors of the semiconductor "black arts" associated with the deposition of pristine films of nanoscale dimensionality onto enormous Si wafers with near infinite precision. The Si heterostructure story necessarily begins with materials, and circuit designers would do well to remember that much of what they take for granted in transistor performance owes a great debt to the smelters of the crystalline world. This chapter summarizes the key steps in the development of Si-germanium (Gee) –Si strained layer epitaxial. Carbon-doping of epitaxial silicon–germanium (SiGe) layers as a means to effectively suppress boron out-diffusion during fabrication has rapidly become the preferred approach for commercial SiGe technologies, particularly those above first-generation performance levels. The first functional SiGe channel p-channel metal-oxide field-effect transistor (misfit) was published in 1991, and shortly thereafter, a wide variety of other approaches aimed at obtaining the best SiGe pMOSFETs.
