Method of making field effect transistor with higher mobility

摘要

A method of increasing the performance of an FET device by aligning the channel of the FET with the [110] crystal direction of a {100} silicon wafer. The {100} silicon wafer and the image of a lithographic mask are rotated 45 DEG relative to each other so that, instead of the channel being aligned parallel with the [100] crystal direction in the conventional fabrication, the channel is aligned approximately parallel with the [110] crystal direction. The mobility of the carriers is higher in the [110] crystal direction thereby increasing the performance of the FET with only a minor modification in the lithographic process. The novel FET results with its channel aligned approximately parallel with the [110] crystal direction.