| 摘要 |
<P>PROBLEM TO BE SOLVED: To increase a threshold voltage while decreasing on-resistance in a transistor using a nitride semiconductor layer as a channel. <P>SOLUTION: Compression strain is generated at a boundary surface between a cap layer 400 and a barrier layer 300, and at a boundary surface between a channel layer 200 and a buffer layer 100. Stretching strain is generated at a boundary surface between the barrier layer 300 and the channel layer 200. Because of this, the number of negative charges is larger than the number of positive charges at the boundary surface between the cap layer 400 and the barrier layer 300, and at the boundary surface between the channel layer 200 and the buffer layer 100. And the number of the positive charges is larger than the number of the negative charges at the boundary surface between the barrier layer 300 and the channel layer 200. The channel layer 200 includes a lamination structure having a first layer, a second layer and a third layer. The second layer has electron affinity larger than that of each of the first layer and the third layer. <P>COPYRIGHT: (C)2013,JPO&INPIT |
