摘要:
A dielectrically isolated semiconductor wafer substrate includes first and second semiconductive layers bonded to each other by a direct bonding technique in such a manner that an insulative layer is sandwiched therebetween. The first semiconductive layer is a first silicon layer having a (100) or (110) crystal surface orientation, while the second semiconductive layer is a second silicon layer having a (111) crystal surface orientation. Thereafter, a peripheral portion of the resultant substrate is removed, and a substrate of a slightly smaller size is obtained which is provided with an additionally formed new orientation flat.
摘要:
A conductivity-modulation MOSFET employs a substrate (30) of an N type conductivity as its N base. A first source layer (34) of a heavily-doped N type conductivity is formed in a P base layer (32) formed in the N base (30). A source electrode (38) electrically conducts the P base (32) and the source (34). A first gate electrode (36) insulatively covers a channel region (CH1) defined by the N⁺ source layer (34) in the P base (32). A P drain layer (44) is formed on an opposite substrate surface. An N⁺ second source layer (46) is formed in a P type drain layer (44) by diffusion to define a second channel region (CH2). A second gate electrode (40) insulatively covers the second channel region (CH2), thus providing a voltage-controlled turn-off controlling transistor. A drain electrode (48) of the MOSFET conducts the P type drain (44) and second source (46). When the turn-off controlling transistor is rendered conductive to turn off the MOSFET a "shorted anode structure" is temporarily formed wherein the N type base (30) is short-circuited to the drain electrode (48), whereby case, the flow of carriers accumulated in the N type base (30) into the drain electrode is facilitated to accelerate dispersion of carriers upon turn-off of the transistor.
摘要:
A semiconductor device includes a semiconductor substrate, a pair of low breakdown voltage elements formed in the substrate so as to be adjacent to each other, and a high breakdown voltage element formed to be adjacent to one of the low breakdown voltage elements. The pair of low breakdown voltage elements are isolated from each other by a pn junction and the one of the low breakdown voltage elements and the high breakdown voltage element are isolated from each other by a dielectric material. The semiconductor substrate is a composite substrate formed by directly bonding a first substrate serving as an element region to a second substrate serving as a supporting member through an insulating film.
摘要:
Disclosed is a method of manufacturing a semiconductor device, comprising the step of forming a semiconductor wafer having a first impurity-doped layer and a second impurity-doped layer having a higher impurity concentration than that of the first impurity-doped layer, comprising the steps of bringing a first semiconductor substrate (11), having a third impurity-doped layer (12) which has a higher impurity concentration than that of the first impurity-doped layer and the same conductivity type as that of the second impurity-doped layer, and whose surface is mirror-polished, into contact with a second semiconductor substrate (13) having a fourth impurity doped layer, which has a higher impurity concentration than that of the first impurity-doped layer and the same conductiviey type as that of the second impurity-doped layer, and whose surface is mirror-polished, so that the mirror-polished surfaces thereof are in contact with each other, and in a clean atmosphere so that virtually no foreign substances are present therebetween, and annealing the first and second semiconductor substrates (11,13) whose mirror-polished surfaces are in contact with each other at a temperature of not less than 200°C so as to bond them together, thereby forming the second impurity-doped layer consisting of the third and fourth impurity-doped layers.
摘要:
A gate turn-off thyristor drive system with low power loss when it is in the turn-off mode, is disclosed. A first turn-off pulse of a predetermined amplitude is applied to a first gate electrode (16). A second turn-off pulse is applied to a second gate electrode (18). An amplitude of the second turn-off pulse is smaller in absolute value than that of the first turn-off pulse. The fall time of the anode current at the time of turn-off is reduced, and the initial value of the tail current of the anode current is reduced. The power loss as the product of the anode voltage and the anode current is reduced.
摘要:
A semiconductor device includes a semiconductor substrate, a pair of low breakdown voltage elements formed in the substrate so as to be adjacent to each other, and a high breakdown voltage element formed to be adjacent to one of the low breakdown voltage elements. The pair of low breakdown voltage elements are isolated from each other by a pn junction and the one of the low breakdown voltage elements and the high breakdown voltage element are isolated from each other by a dielectric material. The semiconductor substrate is a composite substrate formed by directly bonding a first substrate serving as an element region to a second substrate serving as a supporting member through an insulating film.
摘要:
A dielectrically isolated semiconductor wafer substrate includes first and second semiconductive layers bonded to each other by a direct bonding technique in such a manner that an insulative layer is sandwiched therebetween. The first semiconductive layer is a first silicon layer having a (100) or (110) crystal surface orientation, while the second semiconductive layer is a second silicon layer having a (111) crystal surface orientation. Thereafter, a peripheral portion of the resultant substrate is removed, and a substrate of a slightly smaller size is obtained which is provided with an additionally formed new orientation flat.