Growth and doping of bulk GaN by hydride vapor phase epitaxy*

Abstract

Doping is essential in the growth of bulk GaN substrates, which could help control the electrical properties to meet the requirements of various types of GaN-based devices. The progresses in the growth of undoped, Si-doped, Ge-doped, Fe-doped, and highly pure GaN by hydride vapor phase epitaxy (HVPE) are reviewed in this article. The growth technology and precursors of each type of doping are introduced. Besides, the influence of doping on the optical and electrical properties of GaN are presented in detail. Furthermore, the problems caused by doping, as well as the methods to solve them are also discussed. At last, highly pure GaN is briefly introduced, which points out a new way to realize high-purity semi-insulating (HPSI) GaN.

Vertical GaN Shottky barrier diode with thermally stable TiN anode*

“…Therefore, the dispersion effect of vertical GaN SBD is weak even at the frequency of 038101-3 1 MHz because of the good interface quality between TiN and GaN. [19] without bias…”

Evolution of V-pits in the ammonothermal growth of GaN on HVPE-GaN seeds

“…Nowadays, hydride vapor phase epitaxy (HVPE) is primarily the growth method for commercial bulk GaN substrates because of its high growth rate (up to hundreds of micrometers per hour), and the ability to grow large-size wafers (up to Φ175 mm). 9–11 HVPE is known to be a suitable growth technique for the fabrication of free-standing GaN wafers due to its high growth rate and high quality. However, the generation of pit-type defects in the growth is still an unresolved question.…”

Influence of Polarities of GaN Substrates on Surface Morphologies and Physical Properties of Epitaxial Mg‐Doped GaN Films Grown by MOCVD

“…However, in Mg‐doped GaN, not only the energy level of Mg acceptor is relatively deep in GaN, but also Mg acceptor is easily passivated by H; therefore, the activation efficiency of Mg in GaN is very low, especially for the semipolar and nonpolar Mg‐doped GaN. [ 3,4 ]…”