Abstract: A semiconductor device including: a channel layer; a spacer layer; an intermediate layer; and a barrier layer. The channel layer includes a first nitride semiconductor. The spacer layer includes a second nitride semiconductor having a larger band gap than a band gap of the first nitride semiconductor. The spacer layer is provided on the channel layer. The intermediate layer includes Alx1Iny1Ga(1-x1-y1)N(0<x1<1, 0<y1<1, and 0<x1+y1<1). The intermediate layer is provided on the spacer layer. The barrier layer includes Alx2In(1-x2)N(0<x2<1). The barrier layer is provided on the intermediate layer.

Abstract: A semiconductor device includes a barrier layer, a channel layer, a regrowth layer, a vacancy generation region, and a source electrode or a drain electrode. The barrier layer includes a first nitride semiconductor. The channel layer includes a second nitride semiconductor and is bonded to the barrier layer at a first surface. The regrowth layer includes an n-type nitride semiconductor and is provided in a region dug deeper than an interface between the barrier layer and the channel layer from a second surface of the barrier layer. The second surface is on opposite side to the first surface. The vacancy generation region includes a nitrogen-capturing element and is provided in a region of the regrowth layer shallower than the interface between the barrier layer and the channel layer. The source electrode or the drain electrode is provided on the regrowth layer.

Abstract: Silicon wafers having a density of BMDs with sizes between 20 to 40 nm at positions ?20 ?m below the wafer surface in the range of 5×1011/cm3, and a density of BMDs with sizes of ?300 nm?1×107/cm3, exhibit reduced slip dislocation and warpage. The wafers are sliced from a crystal grown under specific conditions and then subjected to both low temperature heat-treatment and high temperature anneal.

Abstract: Silicon wafers and a process for their manufacture wherein both slip dislocation and occurrence of warpage are suppressed include heat treatment to provide wafers having plate-shaped BMDs, a density of BMDs whose diagonal lengths are in a range of 10 nm to 120 nm, of BMDs present in the bulk of the wafer at a distance of 50 ?m or more is 1×1011/cm3 or more, and the density of BMDs whose diagonal lengths are 750 nm or more in the wafer bulk is 1×107/cm3 or less, and the interstitial oxygen concentration is 5×1017 atoms/cm3 or less. The process involves low and high temperature heat treating at under defined temperature ramping rates.

Abstract: An x-ray generator comprising a vessel 1 in which a low pressure gas atmosphere is maintained, hemimorphic crystal supporting means 3a and 3b provided in the vessel, at least a pair of hemimorphic crystals 5a and 5b arranged oppositely at an interval and supported by the hemimorphic crystal supporting means in the vessel, and means 3a, 3b; 6b to 8a and 8b for elevating and lowering the temperature of the hemimorphic crystals. X-rays are radiated from the vessel as the temperature of the hemimorphic crystals is elevated or lowered.

Abstract: Silicon wafers and a process for their manufacture wherein both slip dislocation and occurrence of warpage are suppressed include heat treatment to provide wafers having plate-shaped BMDs, a density of BMDs whose diagonal lengths are in a range of 10 nm to 120 nm, of BMDs present in the bulk of the wafer at a distance of 50 ?m or more is 1×1011/cm3 or more, and the density of BMDs whose diagonal lengths are 750 nm or more in the wafer bulk is 1×107/cm3 or less, and the interstitial oxygen concentration is 5×1017 atoms/cm3 or less. The process involves low and high temperature heat treating at under defined temperature ramping rates.

Abstract: Silicon wafers having a density of BMDs with sizes between 20 to 40 nm at positions ?20 ?m below the wafer surface in the range of 5×1011/cm3, and a density of BMDs with sizes of ?300 nm?1×107/cm3, exhibit reduced slip dislocation and warpage. The wafers are sliced from a crystal grown under specific conditions and then subjected to both low temperature heat-treatment and high temperature anneal.

Abstract: An x-ray generator comprising a vessel 1 in which a low pressure gas atmosphere is maintained, hemimorphic crystal supporting means 3a and 3b provided in the vessel, at least a pair of hemimorphic crystals 5a and 5b arranged oppositely at an interval and supported by the hemimorphic crystal supporting means in the vessel, and means 3a, 3b; 6b to 8a and 8b for elevating and lowering the temperature of the hemimorphic crystals. X-rays are radiated from the vessel as the temperature of the hemimorphic crystals is elevated or lowered.