Semiconductor device and method of manufacturing the same

A semiconductor device comprising:

• a first electrode;
• a second electrode;
• a third electrode, a position of the third electrode in a first direction from the first electrode to the second electrode being between a position of the first electrode in the first direction and a position of the second electrode in the first direction;
• a semiconductor member including a first semiconductor region and a second semiconductor region,
• the first semiconductor region including Alx1Ga1−x1N (0≤x1<1), the first semiconductor region including a first partial region, a second partial region, a third partial region, a fourth partial region, and a fifth partial region, a second direction from the first partial region to the first electrode crossing the first direction, a direction from the second partial region to the second electrode being along the second direction, a direction from the third partial region to the third electrode being along the second direction, a position of the fourth partial region in the first direction being between a position of the first partial region in the first direction and a position of the third partial region in the first direction, a position of the fifth partial region in the first direction being between the position of the third partial region in the first direction and a position of the second partial region in the first direction,
• the second semiconductor region including Alx2Ga1−x2N (0<x2≤1, x1<x2), the second semiconductor region including a first semiconductor portion and a second semiconductor portion, a direction from the fourth partial region to the first semiconductor portion being along the second direction, a direction from the fifth partial region to the second semiconductor portion being along the second direction;
• a first compound member including aluminum, silicon and oxygen, the first compound member including a first compound region, a second compound region and a third compound region, the first compound region being between the fourth partial region and at least a part of the third electrode in the first direction, the second compound region being between the at least the part of the third electrode and the fifth partial region in the first direction, the third compound region being between the third partial region and the third electrode in the second direction;
• and
• an intermediate region being between the third partial region and the third compound region, the intermediate region including a first intermediate portion and a second intermediate portion, the second intermediate portion being between the first intermediate portion and the third compound region in the second direction, the first intermediate portion including Ga, N, O and Al, the second intermediate portion including Ga, N, O, Al and Si, the first intermediate portion not including Si, or a concentration of Si at the first intermediate portion being lower than a concentration of Si at the second intermediate portion.

A method of manufacturing a semiconductor device, the method comprising:

• preparing a first structure body, the first structure body including a base semiconductor layer being a part of a semiconductor member, and a first compound member, the base semiconductor layer including Alx3Ga1−x3N (0≤x3<1) and including an upper face, the first compound member being provided on the upper face and including aluminum, silicon, and oxygen;
• removing a part of the first compound member to expose a part of the base semiconductor layer,
• growing an other part of the semiconductor member from the exposed part of the base semiconductor layer, the semiconductor member including a first semiconductor region provided on the part of the base semiconductor layer and including Alx1Ga1−x1N (0≤x1<1), and a second semiconductor region provided on the first semiconductor region and including Alx2Ga1−x2N (0<x2<1, x1<x2, x3<x2);
• making a hole in the first compound member after the growing the other part of the semiconductor member;
• and
• filling a conductive member in the hole.