Active device and fabricating method thereof

摘要

An active device and a fabricating method thereof are provided. The active device includes a buffer layer, a channel, a gate, a gate insulation layer, a source and a drain. The buffer layer is disposed on a substrate and has a positioning region. A thickness of a portion of the buffer layer in the positioning region is greater than a thickness of a portion of the buffer layer outside the positioning region. The channel is disposed on the buffer layer and in the positioning region. The gate is disposed above the channel. The gate insulation layer is disposed between the channel and the gate. The source and the drain are disposed above the channel and electrically connected to the channel.

主权项

1. A method for fabricating an active device, comprising:
forming a buffer layer on a substrate; forming a channel material layer on the buffer layer; forming a channel, wherein the buffer layer having a positioning region, a thickness of a portion of the buffer layer in the positioning region is greater than a thickness of a portion of the buffer layer outside the positioning region, and the channel is disposed on the buffer layer and in the positioning region, and wherein the channel and a portion of the buffer layer below the channel together form an alignment mark corresponding to the positioning region; after the step of forming the alignment mark, forming a gate insulation layer entirely covering the channel and the buffer layer so that light transmittances of the positioning region and outside the positioning region are different; using the alignment mark by the different light transmittances to form a gate on the gate insulation layer which is entirely covering the channel and the buffer layer; and forming a source and a drain that are above the channel and electrically connected to the channel.