Fluorine Plasma Ion Implantation Technology: a New Dimension in GaN Device Processing

The recent discovery of the potential and charge modulation by fluorine ions incorporated in III-nitride heterojunction FETs has opened up numerous new opportunities of realizing desired device performance and fabricating integrated circuits with desirable circuit configurations. The most significant development based on the fluorine plasma ion implantation technology is the demonstration of self-aligned enhancement-mode (E-mode) AlGaN/GaN HEMT (high electron mobility transistors) that exhibits low on-resistance and low knee-voltage. In this paper, a comprehensive overview of the fluorine plasma ion implantation technology is presented. The discussions will focus on: 1) underlying physical mechanisms; 2) detailed dc and RF device characteristics; 3) circuit applications in wireless communication, high temperature electronics and power electronics and; and 4) reliability of fluorine ions in III-nitride semiconductors.