Low-temperature-grown GaAs enhanced wet thermal oxidation of Al0.98Ga0.02As

Abstract

The effects of incorporating low-temperature-grown GaAs (LT GaAs) into the layer structure of Al0.98Ga0.02As/GaAs are studied. Results show that the structures containing a 300 nm layer of LT GaAs have faster oxidation rates and lower oxidation temperatures compared to reference samples without the LT GaAs layer. This letter will discuss the mechanisms involved in the oxidation rate increase, attributed to the LT GaAs enhancing the transport of As species during the oxidation process.

Influence of Low Temperature-Grown GaAs on Lateral Thermal Oxidation of Al0.98Ga0.02As

“…AsH 3 is a material which was assumed to escape to the surface: However our results show that a significant amount of As remains in the sample after oxidation suggesting that either arsine decomposes [7]: 2AsH 3 2As + 3H 2 (4) Or that direct formation of As and H 2 takes place by substitution of reaction (4) in (1), (2) and (3).…”

“…In this work we study the structural changes resulting from the inclusion of a low-temperature (LT) GaAs layer. The effects of the presence of a LT-GaAs on the oxidation rates was reported previously [4] indicating a higher oxidation rate for samples including LT-GaAs layers. The influence of the incorporation of a SiO 2 capping layer on the quality of the oxide layer is also discussed.…”

“…Another interesting feature is the faster oxidation rate of the sample with the LT GaAs layer (21 µm in 10 min.) compared to the standard sample (10 µm in the same time) [4].…”

Strain relaxation in InGaAs lattice engineered substrates

“…The LT GaAs buffer was grown beneath the AlAs layer to assist in oxidation. 14 The strained In x Ga 1-x As layers were grown directly on the AlAs oxidation layers. The thicknesses of the different In x Ga 1-x As layers used were 1000 Å In 0.2 Ga 0.8 As grown at 430°C, 760 Å In 0.3 Ga 0.7 As grown at 400°C and 480 Å In 0.4 Ga 0.6 As grown at 300°C, respectively.…”

Improvement of InGaAs/GaAs vertical-cavity surface-emitting lasers by post-oxidation annealing

“…The thermal selective wet oxidation confinement technique is widely used to fabricate infrared VCSELs such as 850 and 980 nm VCSELs [4,5] . Various papers have reported the control of thermal wet oxidation processing conditions [6,7] . Stable lateral oxidation is achieved by wet oxidation at 380-430…”