Polycrystalline GaN layer recrystallization by metal‐induced method during the baking process

Abstract

Radio frequency reactive sputtering was used to produce gallium nitride films on thermally oxidized silicon substrates at room temperature. Metallic Ga (purity 6N) was used as the target, N 2 and Ar were utilized as sputtering gases. Amorphous GaN was obtained by metal-induced crystallization with a Ni assistance. The nickel particles were scattered onto the surface by rf sputtering and their density was 2 x 10 14 atoms/cm 2 or 4 x 10 14 atoms/cm 2 , which corresponds to 0.02 nm and 0.04 nm thick layer. These values are less than a monolayer thickness, so they are not continuous. Samples were annealed at 700 ºC for 3 h and at 900 ºC for 5 min in a RTP furnace. The 2.5 µm GaN layers grown on the Ni-coated SiO 2 surface recrystalized during annealing forming crystals of (002) orientation. The catalytic regrowth mechanism of GaN is discussed on the basis of experimental results.

Spectroscopic ellipsometry studies of GaN films deposited by reactive rf sputtering of GaAs target

“…1,8 However, owing to their enormous application potential, there has recently been increasing interest in polycrystalline GaN films grown by MBE, [9][10][11][12][13][14] MOCVD, [15][16][17][18] and sputtering. [19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36] Polycrystalline, 19 nanocrystalline, 20 and amorphous 37 GaN have also shown good luminescence characteristics. Applications of polycrystalline GaN films have been demonstrated in LEDs, 38,39 white lighting, 39 UV photodetectors, 40 solar cells, 41,42 thin film transistors, 43,44 and field electron emitters, 16,45 and suitability of GaN films for application in large area flat panel displays has also been explored.…”

“…There have been several early reports on the growth of GaN films by reactive sputtering of Ga target with nitrogen or nitrogenargon mixture, [21][22][23] though problems of reproducibility arising out of the low melting temperature of gallium have been reported. 24 During the past few years, polycrystalline GaN films have been deposited by sputtering using Ga, [25][26][27][28] GaN, [29][30][31][32][33][34] or GaAs ͑Ref. 35͒ targets.…”

Highly oriented GaN films grown on ZnO buffer layer over quartz substrates by reactive sputtering of GaAs target

“…There have been several early reports on the growth of GaN films by reactive sputtering of Ga target with nitrogen or nitrogen-argon mixture [35][36][37], though problems of reproducibility arising out of the low melting temperature of gallium have been reported [38]. However, during the last few years, GaN films have been deposited using both Ga [18][19][20][21][22] or GaN [23][24][25][26][27][28] targets. The growth of GaN films has also been reported [29,39] by reactive sputtering of a GaAs target with 100% nitrogen.…”