Surface and Interfacial Reaction Study of Half Cycle Atomic Layer Deposited Al$_{2}$O$_{3}$ on Chemically Treated InP Surfaces

Abstract

The interfacial reactions between atomic layer deposited Al 2 O 3 films on various chemically treated InP(100) surfaces have been investigated by in situ X-ray photoelectron spectroscopy at each half cycle in the deposition process. With the first cycle of trimethyl aluminum, a significant decrease in the amount of indium oxides present on the surface is seen, consistent with the ''clean up'' effect reported for other III-V semiconductor surfaces. However, a concurrent increase in the amount of phosphorous oxide is seen, suggesting oxygen transfer from indium oxides to phosphorous during indium oxide decomposition. #

Silicon solar cells with Al2O3 antireflection coating

“…A unique advantage of ALD method is the ability to uniformly deposit on geometrically complex surfaces [9][10][11]. For this reason, atomic layer deposition method may be used for deposition of the optical thin film on the silicon solar cells as antireflection coating.…”

In situ study of the role of substrate temperature during atomic layer deposition of HfO2 on InP

“…7 One of the advantages of high-k dielectrics grown by atomic layer deposition (ALD) on III-V substrates is the "self cleaning" effect, 7 in which the native oxides are converted by the first pulse of metal precursor during ALD. 8,9 Suri et al have shown, using tetrakis(dimethylamido)hafnium (TDMA-Hf) and H 2 O precursors, that the "self cleaning" effect on GaAs is temperature dependent, with the removal of oxides being more pronounced at 300 C than at the 250 C or 200 C. 10 However, quite different trends for the "self cleaning" effect have been reported on GaAs in comparison to those for acid etched and S-passivated InP. 9,11,12 A less efficient "self cleaning" effect has been observed during thin film deposition (2 nm) of ALD HfO 2 , while the "self cleaning" effect has been reported to be enhanced significantly following thick (8 nm) ALD using tetrakis(ethylmethylamino)hafnium (TEMA-Hf) and water as precursors at a substrate temperature of 300 C. 7 Recently, An et al 13 reported the impact of ALD temperature on HfO 2 deposition on S-passivated InP substrates using TEMA-Hf and water, with a significant "self cleaning" effect occurring at 200 C and 250 C but substantial InP substrate oxidation occurring at 300 C. 13 This apparent variation during ALD HfO 2 on different III-V substrate materials therefore warrants further study.…”

“…14 Actually, recent in situ "half cycle" studies of ALD HfO 2 and Al 2 O 3 on native oxide and chemically treated InP (100) have shown that no "self cleaning" effect takes place on P-oxides during the initial ALD process. 9,15 In this study, the in situ evolution of a high-k/native oxide and wet chemically treated InP (100) interface during ALD at temperatures of 200 C, 250 C, and 300 C is reported, and the role of ALD temperature in the removal of InP (100) interfacial oxides during the initial stages using TDMA-Hf and water is investigated.…”

Post deposition annealing effect on the properties of Al2O3/InP interface

“…6 It was observed for Al 2 O 3 ALD on InP that most of the In-oxide concentration decrease (due to self-cleaning) and complete P-oxide chemical state transformation into more P-rich oxide state took place during the first pulse of TMA. 7 The electrical characteristics of ALD TiO 2 /Al 2 O 3 /(NH 4 ) 2 S-treated InP showed the removal of native oxides by the (NH 4 ) 2 S treatment and ALD-Al 2 O 3 self-cleaning. 8 On the basis of the reported self-cleaning data, it was suggested that the native oxide in the 2 nm thick HfO 2 /InP would be removed entirely during the ALD process.…”