OPTICAL IN-SITU ANALYSIS OF GAAS ALAS/GAAS AND GAAS/(AL)GAAS/GAAS ATOMIC LAYER GROWTH USING GACL(3), ALCL(3) AND ASH(3)/

Atomic layer growth of AlAs and AlGaAs were tried by alternate supply of GaCl3, AlCl3 and AsH3, and the growth process was monitored by an o ptical method such as the surface photo-absorption (SPA) method and th e optical interference method. Although atomic layer epitaxy (ALE) of GaAs can be performed by alternate supply of GaCl3 and AsH3, that of A lAs on GaAs could not be obtained, probably due to surface oxidation o f AlAs. AlAs, however, could be grown by simultaneous supply of AlCl3 and AsH3. It was confirmed by the SPA signal that if the AlCl3-adsorbe d AlAs surface is exposed to GaCl3, the adsorbed AlCl3 is replaced by GaCl and/or GaCl and GaAs ALE growth on AlAs can be performed. A sligh tly Al-containing (Al)GaAs layer could be grown by addition of AlCl3 t o GaCl3 in GaAs ALE growth.