Semiconductor device and method for controlling same

A method for controlling a semiconductor device,

• the device including:
• a first semiconductor layer of a first conductivity type;
• a second semiconductor layer provided on the first semiconductor layer, the second semiconductor layer being of a second conductivity type;
• a third semiconductor layer provided selectively on the second semiconductor layer, the third semiconductor layer being of the first conductivity type;
• a fourth semiconductor layer provided selectively on the second semiconductor layer, the fourth semiconductor layer being of the second conductivity type, the third and fourth semiconductor layers being arranged along the second semiconductor layer;
• a fifth semiconductor layer of the second conductivity type, the first semiconductor layer being provided between the second semiconductor layer and the fifth semiconductor layer;
• a first control electrode provided in a first trench, the first trench extending into the first semiconductor layer from an upper surface of the third semiconductor layer, the first control electrode being electrically insulated from the first, second, and third semiconductor layers by a first insulating film, the second semiconductor layer facing the first control electrode via the first insulating film, the third semiconductor layer contacting the first insulating film;
• a first electrode electrically connected to the third semiconductor layer;
• a second electrode electrically connected to the fourth semiconductor layer, the second electrode being electrically isolated from the first electrode;
• a third electrode electrically connected to the fifth semiconductor layer;
• and
• a control terminal electrically connected to the first control electrode,
• the method comprising:
• setting a potential connected to the fourth semiconductor layer via the second electrode to be less than a potential connected to the third semiconductor layer via the first electrode.

A method for controlling a semiconductor device,

• the device including:
• a first semiconductor layer of a first conductivity type;
• a second semiconductor layer provided on the first semiconductor layer, the second semiconductor layer being of a second conductivity type;
• a third semiconductor layer provided selectively on the second semiconductor layer, the third semiconductor layer being of the first conductivity type;
• a fourth semiconductor layer provided selectively on the second semiconductor layer, the fourth semiconductor layer being of the second conductivity type, the third and fourth semiconductor layers being arranged along the second semiconductor layer;
• a fifth semiconductor layer of the second conductivity type, the first semiconductor layer being provided between the second semiconductor layer and the fifth semiconductor layer;
• a first control electrode provided in a first trench extending in the first semiconductor layer from an upper surface of the third semiconductor layer, the first control electrode being electrically insulated from the first, second, and third semiconductor layers by a first insulating film, the second semiconductor layer facing the first control electrode via the first insulating film, the third semiconductor layer contacting the first insulating film;
• a first electrode electrically connected to the third semiconductor layer;
• a second electrode electrically connected to the fourth semiconductor layer;
• a third electrode electrically connected to the fifth semiconductor layer;
• and
• a control terminal electrically connected to the first control electrode,
• the method comprising:
• setting a potential connected to the fourth semiconductor layer via the second electrode to be less than a potential connected to the third semiconductor layer via the first electrode when a voltage between the first electrode and the third electrode exceeds a prescribed value.