High voltage operating field effect transistor, and bias circuit therefor and high voltage circuit thereof

A high voltage operating field effect transistor, comprising:

• a substrate;
• a semiconductor channel formation region disposed in a surface of the substrate;
• a source region and a drain region which are spaced apart from each other with the semiconductor channel formation region disposed between the source region and the drain region;
• a gate insulating film region disposed on the semiconductor channel formation region;
• a resistive gate region disposed on the gate insulating film region;
• a source side electrode disposed on a source region side of the resistive gate region and being operative to receive a signal electric potential;
• and
• a drain side electrode disposed on a drain region side of the resistive gate region and being operative to receive a bias electric potential an absolute value of which is equal to or larger than that of a specified electric potential and which changes according to an increase or decrease in a drain electric potential.

A method of high voltage operation of a field effect transistor, comprising:

• providing a field effect transistor that includes a substrate, a semiconductor channel formation region disposed in a surface of the substrate, a source region and a drain region which are spaced apart from each other with the semiconductor channel formation region disposed between the source region and the drain region, a gate insulating film region disposed on the semiconductor channel formation region, a resistive gate region disposed on the gate insulating film region, a source side electrode disposed on a source region side of the resistive gate region, and a drain side electrode disposed on a drain region side of the resistive gate region;
• supplying a signal electric potential to the source side electrode of the field effect transistor;
• and
• supplying to the drain side electrode of the field effect transistor a bias electric potential an absolute value of which is equal to or larger than that of a specified electric potential and which changes according to an increase or decrease in a drain electric potential.