Patent ID: 7825434
Filing Date: 2010-11-02
Classification: H01L

Abstract:
1. A nitride semiconductor device, comprising: a first semiconductor layer made of first nitride semiconductor; a second semiconductor layer formed on a principal surface of the first semiconductor layer and made of second nitride semiconductor having a bandgap wider than that of the first nitride semiconductor, said second nitride semiconductor includes Al a control layer selectively formed on an upper portion of the second semiconductor layer and made of third nitride semiconductor having a p-type conductivity; source and drain electrodes formed on the second semiconductor layer at respective sides of the control layer; and a fourth semiconductor layer formed on a surface of the first semiconductor layer opposite to the principal surface, having a potential barrier in a valence band with respect to the first nitride semiconductor and made of fourth nitride semiconductor containing aluminum, wherein: a the channel region is formed in the first semiconductor layer, the control layer controls electrical conductivity between the source electrode and the drain electrode, the nitride semiconductor device is of a normally OFF type, and a thickness of the control layer is greater than a thickness of the second semiconductor layer.