Semiconductor substrate, method for manufacturing semiconductor substrate and method for manufacturing semiconductor device

A method for manufacturing a semiconductor substrate comprising the steps of:

• preparing a base substrate;
• forming a removal layer, of which at least a portion is to be removed by performing etching, on the base substrate;
• forming a semiconductor epitaxial layer above the removal layer;
• and
• providing a support member for supporting the semiconductor epitaxial layer in a state where the support member is in contact with side surfaces of the base substrate, the removal layer, and the semiconductor epitaxial layer such that the semiconductor epitaxial layer is positioned above the base substrate, after forming the semiconductor epitaxial layer, the thickness of at least a portion of a region of the support member in contact with the removal layer being smaller than the thickness of other regions that are different from the at least the portion of the region in the support member, the support member being cut off in a region in contact with the removal layer due to application of a force to the semiconductor epitaxial layer, further comprising:
• removing at least a portion of the removal layer by performing etching using a predetermined etching material, and
• cutting off the support member by applying a force in a direction in which the semiconductor epitaxial layer moves away from the base substrate.

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

• preparing a semiconductor, wherein the semiconductor substrate comprising:
• a base substrate;
• a removal layer that is provided on the base substrate, and of which at least a portion is to be removed by performing etching;
• a semiconductor epitaxial layer that is provided above the removal layer;
• a support member for supporting the semiconductor epitaxial layer in a state where the support member is in contact with side surfaces of the base substrate, the removal layer, and the semiconductor epitaxial layer such that the semiconductor epitaxial layer is positioned above the base substrate, the support member being cut off in a region in contact with the removal layer due to application of a force to the semiconductor epitaxial layer, wherein
• the thickness of at least a portion of a region of the support member in contact with the removal layer is smaller than the thickness of other regions that are different from the at least the portion of the region in the support member;
• removing at least a portion of the removal layer by performing etching using a predetermined etching material;
• cutting off the support member by applying a force in a direction in which the semiconductor epitaxial layer moves away from the base substrate after the removing;
• and
• bonding the semiconductor epitaxial layer to a destination substrate that is different from the base substrate after the cutting off.

A semiconductor substrate, comprising:

• a base substrate;
• a removal layer that is provided on the base substrate, and of which at least a portion is to be removed by performing etching;
• a semiconductor epitaxial layer that is provided above the removal layer;
• a support member for supporting the semiconductor epitaxial layer in a state where the support member is in contact with side surfaces of the base substrate, the removal layer, and the semiconductor epitaxial layer such that the semiconductor epitaxial layer is positioned above the base substrate, the support member being cut off in a region in contact with the removal layer due to application of a force to the semiconductor epitaxial layer, wherein
• the thickness of at least a portion of a region of the support member in contact with the removal layer is smaller than the thickness of other regions that are different from the at least the portion of the region in the support member, wherein
• the base substrate is composed of InP,
• the semiconductor epitaxial layer is In1-xGaxAsyP1-y (0≤x, y≤1), and
• the removal layer is a semiconductor layer that lattice-matches on the base substrate.