Semiconductor device

A semiconductor device, comprising:

• a semiconductor layer including a first surface and a second surface, the second surface being positioned at a side opposite to the first surface in a first direction;
• and
• a trench structure part positioned inside the semiconductor layer, the trench structure part extending in the first direction from the first surface,
• the trench structure part including
• a gate electrode,
• a conductive member including a lower end portion, the lower end portion being positioned more proximate to the second surface than the gate electrode in the first direction, and
• an insulating member positioned between the gate electrode and the semiconductor layer, between the conductive member and the semiconductor layer, and between the gate electrode and the conductive member, the insulating member including a fixed charge,
• the insulating member including a first insulating part positioned between the gate electrode and the second surface in the first direction and positioned between the conductive member and the semiconductor layer in a second direction crossing the first direction,
• the first insulating part including a first region, a second region, and a third region,
• the first region being positioned between the gate electrode and the second region in the first direction,
• the second region being positioned between the first region and the third region in the first direction,
• the third region being positioned between the second region and the second surface in the first direction,
• a density of the fixed charge being greater in the first region than in the second region.

A semiconductor device, comprising:

• a semiconductor layer including a first surface and a second surface, the second surface being positioned at a side opposite to the first surface in a first direction;
• and
• a trench structure part positioned inside the semiconductor layer, the trench structure part extending in the first direction from the first surface,
• the trench structure part including
• a gate electrode,
• a conductive member including a lower end portion, the lower end portion being positioned more proximate to the second surface than the gate electrode in the first direction,
• an insulating member positioned between the gate electrode and the semiconductor layer, between the conductive member and the semiconductor layer, and between the gate electrode and the conductive member,
• the insulating member including a first element,
• the first element including at least one selected from the group consisting of hydrogen, helium, and argon,
• the insulating member including a first insulating part positioned between the gate electrode and the second surface in the first direction and positioned between the conductive member and the semiconductor layer in a second direction crossing the first direction,
• the first insulating part including a portion between a position in the first direction of an end portion of the gate electrode at the second surface side in the first direction and a position in the first direction of an end portion of the conductive member at the second surface side in the first direction,
• the first insulating part including a first position internally dividing the portion in a ratio of 1:9, a second position internally dividing the portion in a ratio of 1:1, and a third position internally dividing the portion in a ratio of 9:1,
• a first element concentration being greater at the first position than at the second position,
• the first element concentration being greater at the third position than at the second position.