Abstract: A stack including at least a semiconductor drift layer stacked on a single-crystal diamond substrate having a coalescence boundary, wherein the coalescence boundary of the single-crystal diamond substrate is a region that exhibits, in a Raman spectrum at a laser excitation wavelength of 785 nm, a full width at half maximum of a peak near 1332 cm?1 due to diamond that is observed to be broader than a full width at half maximum of the peak exhibited by a region different from the coalescence boundary, the coalescence boundary has a width of 200 ?m or more, and the semiconductor drift layer is stacked on at least the coalescence boundary.

Abstract: There is provided a novel stack that includes a single-crystal diamond substrate having a coalescence boundary, yet effectively uses the coalescence boundary. A stack comprising at least a semiconductor drift layer stacked on a single-crystal diamond substrate having a coalescence boundary, wherein the coalescence boundary of the single-crystal diamond substrate is a region that exhibits, in a Raman spectrum at a laser excitation wavelength of 785 nm, a full width at half maximum of a peak near 1332 cm?1 due to diamond that is observed to be broader than a full width at half maximum of the peak exhibited by a region different from the coalescence boundary, the coalescence boundary has a width of 200 ?m or more, and the semiconductor drift layer is stacked on at least the coalescence boundary.

Abstract: A surface hardening method for resins and a surface hardened resin, capable of reforming the surface of a plastic disk substrate at low energy in a short time, and a production device of such a resin is disclosed. The formation of an ion-implanted layer 11 by implanting equal to or more than 1017 carbon ions per cm2 into the surface of a plastic disk substrate 10 at equal to or less than 20 KeV and the formation of a thin film 12 of high hardness on the ion-implanted layer 11 can be performed alternately or simultaneously, and the hardening rate is increased further by using a bias device.

Abstract: A laser ablation type ion source including vacuum chambers provided with a retaining section for holding a solid raw material for the generation of ions, an ion extracting electrode, an ion accelerating electrode, and a mass spectrograph for ion separation. The ion source also includes a laser beam source for injecting a laser beam of high density into the vacuum chamber.

Abstract: A material of ions is sputtered with cesium ions to generate negative ions and, the negative ions are accelerated and mass-separated to obtain a negative ion beam, and a material of thin film is sputtered with the negative ion beam, thereby forming a thin film on a base material.