IMPACT IONIZATION IN SHORT ALZGA1–ZN-BASED DIODES

Abstract

The development of millimeter and terahertz wave ranges is one of the main objectives of radiophysics. However, there are not many active elements that can operate in those ranges. Impact ionization in wide gap semiconductors is a fast process and can be used in active elements operating in these ranges. In this paper the charge transfer in short diodes (the length of the active area is less than 0.3 m) is considered. The purpose of the study is to determine the appearance conditions and peculiarities of impact ionization. The influence of impact ionization on devises characteristics is determined. The possibility of creating localized high electric field region is shown. The field magnitude is enough for obtaining impact ionization. It is a possibility to operate the impact ionization by changing the AlzGa1–zN composition distribution along the diode. The result of the study is the determination of properties of impact ionization in the proposed structures. They can be used for further detailed analysis of physical processes of the structures and their manufacturing.

Keywords

• diodes
• domain
• electric field strength
• graded gap layer
• heterojunction
• impact ionization
• impedance