US 9,812,562 B1
Semiconductor structure, HEMT structure and method of forming the same
Yao-Chung Chang, Hsinchu County (TW); Po-Chih Chen, Hsinchu (TW); Jiun-Lei Jerry Yu, Hsinchu County (TW); and Chun Lin Tsai, Hsin-Chu (TW)
Assigned to TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY LTD., Hsinchu (TW)
Filed by TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY LTD., Hsinchu (TW)
Filed on Jun. 3, 2016, as Appl. No. 15/172,775.
Int. Cl. H01L 29/778 (2006.01); H01L 29/20 (2006.01); H01L 29/205 (2006.01); H01L 21/324 (2006.01); H01L 21/02 (2006.01); H01L 29/66 (2006.01)
CPC H01L 29/7787 (2013.01) [H01L 21/02057 (2013.01); H01L 21/3245 (2013.01); H01L 29/2003 (2013.01); H01L 29/205 (2013.01); H01L 29/66431 (2013.01); H01L 29/66462 (2013.01); H01L 29/778 (2013.01); H01L 29/7783 (2013.01); H01L 29/7786 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A semiconductor structure, comprising:
a channel layer;
an active layer over the channel layer, the active layer configured to form a two-dimensional electron gas (2DEG) to be formed in the channel layer along an interface between the channel layer and the active layer;
a gate electrode over a top surface of the active layer; and
a source/drain electrode over the top surface of the active layer;
wherein the active layer includes a first layer at the top surface and a second layer directly under the first layer at a bottom surface thereof, the first layer possessing a higher aluminum (Al) atom concentration compared to the second layer.