Grain size dependent photoresponsivity in GaAs films formed on glass with Ge seed layers

The strong correlation between grain size and photoresponsivity in polycrystalline GaAs films on glass was experimentally demonstrated using Ge seed layers with a wide range of grain sizes (1‒330 μm). The crystal evaluations using Raman spectroscopy, scanning electron microscopy, electron backscatter diffraction, and transmission electron microscopy revealed that 500-nm-thick GaAs films epitaxially grown from the Ge seed layers at 550 °C inherited the grain boundaries and crystal orientations in Ge. With increasing grain size, the photoresponsivity corresponding to GaAs increased from 0.01 to 3 A W−1 under a bias voltage of 0.3 V. The maximum value approached that of the GaAs film formed simultaneously on a single-crystal Ge wafer, indicating the high potential of the large-grained GaAs film. Knowledge gained from this study will be essential for designing advanced solar cells based on polycrystalline III–V compound semiconductors using inexpensive substrates.

MOVPE Growth of Mg-doped GaAs Films

The short research of optimization of the growth method to obtain p-type GaAs (001) layers using Si as the dopant was reported in this work. Atomic force microscopy was used to analyze the surface morphology and low-temperature photoluminescence also used to confirm the p-type of the layers.

Growth and Characterizations of Mg-doped GaAs Films

The short research of optimization of the growth method to obtain p-type GaAs (001) layers using Si as the dopant was reported in this work. Atomic force microscopy was used to analyze the surface morphology and low-temperature photoluminescence also used to confirm the p-type of the layers.

Characterizations of p-type GaAs Films

The short research of optimization of the growth method to obtain p-type GaAs (001) layers using Si as the dopant was reported in this work. Atomic force microscopy was used to analyze the surface morphology and low-temperature photoluminescence also used to confirm the p-type of the layers.