Growth of thick AlN layer on sapphire (0001) substrate using hydride vapor phase epitaxy

Abstract

Growth of thick AlN layer was performed directly on sapphire (0001) substrate at 1100 ºC by hydride vapor phase epitaxy (HVPE) using AlCl 3 and NH 3 as source gases. Growth rate over 10 µm/h was demonstrated by increasing input partial pressure of AlCl 3 . Also, it was found that the growth rate was sensitive to NH 3 input partial pressure ( o NH 3 P ), and decreased rapidly with increase of o NH 3 P . Edge dislocation density estimated from full width at half maximum (FWHM) of X-ray diffraction (XRD) rocking curves was independent of the growth rate.

Thermodynamic and experimental investigations on the growth of thick aluminum nitride layers by high temperature CVD

“…Then, AlN epitaxial layers were obtained by reaction between anhydrous aluminum chloride and ammonia in 1967 and 1968 [5,6] or by direct reaction of the adduct compound AlCl 3 .NH 3 between 1970 and 1977 [7][8][9]. Since 1972, epitaxial growth of AlN on Sapphire and SiC substrates by a vapor phase epitaxy process using Al, HCl and NH 3 have been studied at temperature of about 1100 C [10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28]. Since 2007, several studies have been investigated to increase AlN layers crystalline quality and growth rate by increasing deposition temperature [29][30][31][32][33][34][35].…”

Direct heteroepitaxial growth of thick AlN layers on sapphire substrates by hydride vapor phase epitaxy

“…Refs. [7,9] have estimated their dislocation densities from the FWHM of XRD rocking curves to be approximately 2 Â 10 10 and 10 11 cm À2 , respectively. Although we have succeeded in reducing the defect density by an order of magnitude over recent reports, further reduction is necessary to make these layers suitable as substrates for high-efficiency device growth.…”

“…In either application, HVPE permits the fabrication of AlN substrates of at least 2 in in diameter. Although HVPE is capable of high growth rates, previous attempts to grow AlN films by HVPE have been limited to relatively low growth rates to produce high-quality layers [6][7][8][9][10]. Past efforts to increase the growth rate of AlN layers by this technique have resulted in either poor surface morphology or inferior structural quality.…”

Growth of thick Al Ga1−N ternary alloy by hydride vapor-phase epitaxy

“…This reason is because HVPE growth of Alcontaining materials such as AlN and AlGaN has been generally thought to be difficult due to the violent reaction between the Al source (AlCl) and the quartz (SiO 2 ) reactor. Recently, our group has succeeded in HVPE growth of AlN using AlCl 3 , which does not react with quartz, by controlling Al-precursor molecule [11,12] and we have investigated the growth of thick AlN layer [13,14]. These results suggested the possibility of HVPE growth of Al x Ga 1Àx N ternary alloy by combining with advanced GaN-HVPE.…”