High electron mobility transistor having reduced threshold voltage variation and method of manufacturing the same

摘要

According to example embodiments a transistor includes a channel layer on a substrate, a first channel supply layer on the channel, a depletion layer, a second channel supply layer, source and drain electrodes on the first channel supply layer, and a gate electrode on the depletion layer. The channel includes a 2DEG channel configured to generate a two-dimensional electron gas and a depletion area. The first channel supply layer corresponds to the 2DEG channel and defines an opening that exposes the depletion area. The depletion layer is on the depletion area of the channel layer. The second channel supply layer is between the depletion layer and the depletion area.

主权项

1. A high electron mobility transistor, comprising:
a substrate; a channel layer on the substrate,
the channel layer being a GaN layer,the channel layer including a 2DEG channel and a depletion area; a first channel supply layer on the channel layer and corresponding to the 2DEG channel,
the first channel supply layer defining an opening that exposes the depletion area; a depletion layer on the first channel supply layer and on the depletion area; a second channel supply layer between the depletion layer and the depletion area,
the second channel supply layer including a portion that is on an upper surface of the first channel supply layer and extends over the 2DEG channel,an aluminum (Al) content of the second channel supply layer being different from an aluminum (Al) content of the first channel supply layer,a polarizability of the second channel supply layer being less than a polarizability of the first channel supply layer, andthe first and second channel supply layers both including an aluminum compound; source and drain electrodes spaced apart on the first channel supply layer; and a gate electrode on the depletion layer, wherein the depletion layer is not directly in contact with the first channel supply layer, and the depletion layer is configured to remove a 2DEG that is generated in the depletion area of the channel layer by the second channel supply layer.