Semiconductor device

A semiconductor device comprising:

• a semiconductor layer including a first portion including a first element and oxygen, the first element including at least one selected from the group consisting of In, Ga, Zn, Al, Sn, Ti, Si, Ge, Cu, As, and W;
• and
• a first layer including a second element including at least one selected from the group consisting of W, Ti, Ta, Mo, Cu, Al, Ag, Hf, Au, Pt, Pd, Ru, Y, V, Cr, Ni, Nb, In, Ga, Zn, and Sn,
• the first portion including a first region and a second region,
• the second region being provided between the first region and the first layer,
• the first region including a bond of the first element and oxygen,
• the second region including a bond of the first element and a metallic element,
• a thickness of the first layer along a first direction being not less than 0.5 nm but less than 3 nm, the first direction being from the first portion toward the first layer,
• wherein the first element includes In, and
• wherein a first signal obtained by X-ray photoelectron spectroscopy of the second region includes a first peak at a first binding energy, the first signal at a second binding energy being 20% or more of an intensity of the first peak, the first binding energy being not less than 444 eV and not more than 446 eV, the second binding energy being lower than the first binding energy, and an absolute value of a difference between the first binding energy and the second binding energy being 1.5 eV.

A semiconductor device comprising:

• a semiconductor layer including a first portion including a first element and oxygen, the first element including at least one selected from the group consisting of In, Ga, Zn, Al, Sn, Ti, Si, Ge, Cu, As, and W;
• and
• a first layer including a second element including at least one selected from the group consisting of W, Ti, Ta, Mo, Cu, Al, Ag, Hf, Au, Pt, Pd, Ru, Y, V, Cr, Ni, Nb, In, Ga, Zn, and Sn,
• the first portion including a first region and a second region,
• the second region being provided between the first region and the first layer,
• the first region including a bond of the first element and oxygen,
• the second region including a bond of the first element and a metallic element,
• a thickness of the first layer along a first direction being not less than 0.5 nm but less than 3 nm, the first direction being from the first portion toward the first layer,
• wherein the first element includes Ga, and
• wherein a third signal obtained by X-ray photoelectron spectroscopy of the second region includes a third peak at a fifth binding energy, the third signal at a sixth binding energy being 20% or more of an intensity of the third peak, the fifth binding energy being not less than 1118 eV and not more than 1119 eV, the sixth binding energy being lower than the fifth binding energy, an absolute value of a difference between the fifth binding energy and the sixth binding energy being 2.0 eV.