Proton implant isolation of AlGaInP/GaAs Heterojunction bipolar transistor structures in fabrication

In this paper, proton implant isolation and mask method are studied in Heterojunction bipolar transistor fabrication technology. By means of computation, the best implant dose is determined. After the wafer is annealed, the implant isolation efficiency is better. The best annealing temperature depends on ion implant dose. As temperature continues to rise, its resistivity starts to drop and tends to return to the state before annealing. Both Si3N4 and photoresist are used as double-layer mask, because the technology is simple and reproducibility is reliable, the wafer is not contaminated, implant efficiency and dc performance of the device are good.