Synthesis of GaN bulk crystals and melt growth of GaN layers under nitrogen plasma

Modern Microwave Methods in Solid-State Inorganic Materials Chemistry: From Fundamentals to Manufacturing

“…184 GaN has also been synthesized by plasma methods in a multimode MW via reaction of molten Ga metal previously heated conventionally to 883−973 K. Two stages of treatment were employed: (1) an H 2 plasma and (2) an N 2 plasma so as to eliminate oxide impurities and form the nitride, respectively. 183 Hydrogen and nitrogen plasmas operated at 420 W under pressures of 200 and 200−400 Pa respectively. It was reported that the yield of polycrystalline GaN increased at longer nitrogen plasma exposure times, reaching a yield of 96% of GaN after 3 h; images of the reaction products are shown in Figures 19 and 20.…”

Plasma-assisted electroepitaxy as a method for the growth of GaN layers

“…Wurtzite GaN layers have been synthesized by reacting gallium metal with atomic nitrogen produced by a microwave plasma [6], which avoids the high equilibrium pressure needed for N 2 . Polycrystalline GaN can be synthesized at low equilibrium pressures $ 300 Pa and low temperatures $ 700 1C.…”

Solution growth of GaN on sapphire substrate under nitrogen plasma

“…The 2 g Ga (6 N) in a pyrolytic boron nitride (PBN) crucible (10 mm diameter and 12 mm high) was initially evacuated to 1 Â10 À4 Pa, and was heated at 610-700 1C in the growth chamber. Details of the procedure and setup are described in the previous paper [16]. The plasma mixture of nitrogen and hydrogen was exposed to Ga metal for 240-420 min.…”

“…Our group has developed sub-atmospheric pressure solution growth in which gallium (Ga) metal reacts with atomic nitrogen in a microwave plasma to avoid the high equilibrium pressure and temperature environment [16]. Polycrystalline GaN can be synthesized at low equilibrium pressures of 200-400 Pa and low temperature of 610-700 1C.…”