Hydride Vapor-Phase Epitaxy Reactor for Bulk GaN Growth

TL;DR

This paper presents a newly developed HVPE reactor capable of producing high-quality, large-diameter bulk GaN crystals with improved uniformity, reproducibility, and continuous growth capabilities, using innovative design and materials.

Contribution

The paper introduces a novel HVPE reactor design with advanced features like an axisymmetric gas injector, refractory materials, and external precursors for efficient bulk GaN growth.

Findings

Achieved 1% growth rate non-uniformity

Successfully grew 50 mm diameter freestanding GaN crystals

Implemented features for continuous, reproducible growth

Abstract

An HVPE reactor for the growth of bulk GaN crystals with a diameter of 50 mm was developed. Growth rate non-uniformity of 1% was achieved using an axisymmetric vertical gas injector with stagnation point flow. Chemically-resistant refractory materials were used instead of quartz in the reactor hot zone. High-capacity external gallium precursor sources were developed for the non-stop growth of the bulk GaN layers. A load-lock vacuum chamber and a dry in-situ growth chamber cleaning were implemented to improve the growth process reproducibility. Freestanding GaN crystals with a diameter of 50 mm were grown with the reactor.