TABLE OF CONTENTS Semiconductor processing techniques consist of three basic steps plus several specialised procedures. The basic steps are sample patterning, thin-film deposition and etching (a material removal technique). Specialised techniques include cleaning procedures, dopant introduction methods such as ion implantation and semiconductor regrowth. Excellent texts have been available for many years offering comprehensive coverage of processing techniques as well as equipment and materials used to implement them [13 17]. It is not our intent to reproduce that material in this book; rather we discuss processing techniques in terms of how they affect GaAs device performance and reliability, with special attention to the surfaces and interfaces in these devices. We present critical processing details for a wide variety of situations where the process can affect device performance and reliability but leave comprehensive coverage of most process techniques to other texts.
Processing techniques referred to in this book are introduced closest to the subject matter where they are first required. For example, photolithography is presented in Chapter 4 and rapid thermal annealing is introduced in Chapter 6 and both are referred to in later chapters as well. The reason for this type of presentation is that processing subtleties and interactions occur for most combinations of two or more process steps and examples of these interactions are best given in the appropriate chapter where the complexity becomes apparent.
The remaining processing techniques presented in this chapter are those of back end processing, which are introduced in the next section.
