| 摘要 |
PURPOSE:To increase the number of channels to increase the mutual conductance and to improve the performance index by providing a second gate region in an intermediate depth of a semiconductor layer. CONSTITUTION:A P<-> type semiconductor layer 2 and an N-type epitaxial layer 3 are formed on a semiconductor substrate 1, and an N-type source region 8 and a drain region 9 are formed on the surface of the layer 3. A gate region 5 is formed on the surface of the layer 3, a gate region 6 is also formed in the intermediate depth of the layer 3, and a gate region 7 is also formed on the surface of the layer 2. Thus, the region 6 is formed in the intermediate between the regions 5 and 7 to provide 2 of the conductivity type layers and to increase the mutual conductance gm twice as large as 1 of the number of channel. As a result, performance index gm/Ciss can be improved. |
