Disclosed herein are compositions, methods, and devices. Disclosed herein is a composition comprising a -(Al.sub.xGa.sub.1-x).sub.2O.sub.3, having an x value of less than about 5% and comprising at least one n-carrier dopant. Also disclosed are methods of making the same. Also disclosed are devices comprising the disclosed compositions.

Provided is a method for manufacturing a semiconductor device whose electric characteristics are prevented from being varied and whose reliability is improved. In the method, an insulating film is formed over an oxide semiconductor film, a buffer film is formed over the insulating film, oxygen is added to the buffer film and the insulating film, a conductive film is formed over the buffer film to which oxygen is added, and an impurity element is added to the oxide semiconductor film using the conductive film as a mask. An insulating film containing hydrogen and overlapping with the oxide semiconductor film may be formed after the impurity element is added to the oxide semiconductor film.

The present invention provides a semiconductor structure comprising: a silicon substrate in [100] orientation; a scandium oxide layer over the substrate, in [111] orientation; and a scandium-rare earth-oxide layer over the scandium oxide layer. The scandium-rare earth-oxide layer can have a graded composition to transition lattice constant to match to a subsequent layer, such as an indium nitride layer having very high electron drift velocity. InN over Si (100) offers transistors, photonics and passive electronics that operate in the terahertz frequency range.

An underlying substrate for a single crystal diamond laminate substrate, the underlying substrate including an initial substrate being any of a single crystal Si substrate, a single crystal -Al.sub.2O.sub.3 substrate, etc., and an intermediate layer on the initial substrate, in which an outermost surface on the initial substrate has an off angle in a crystal axis <1-12> direction relative to a cubic crystal plane orientation, or has an off angle in a crystal axis <10-10> or <11-20> direction relative to a hexagonal crystal plane orientation, etc. This provides the underlying substrate capable of forming a single crystal diamond layer having a large area (large diameter), high crystallinity, few hillocks, few abnormal growth particles such as twin crystals, few dislocation defects, etc., high purity, low stress, and high quality and applicable to an electronic and magnetic device.

A semiconductor laminate at least including: a base; a buffer layer; and a crystalline metal oxide semiconductor film containing at least one metal element and having a corundum structure, the semiconductor laminate having the buffer layer on a main surface of the base directly or via another layer, the semiconductor laminate having the crystalline metal oxide semiconductor film on the buffer layer. The buffer layer is a laminate structure of a plurality of buffer films each with a different composition, and at least two buffer films of the plurality of buffer films have a film thickness of 200 nm or more and 650 nm or less.