摘要:
A semiconductor apparatus that has a first parallel pn-layer formed between an active region and an n+-drain region. A peripheral region is provided with a second parallel pn-layer, which has a repetition pitch narrower than the repetition pitch of the first parallel pn-layer. An n−-surface region is formed between the second parallel pn-layer and a first main surface. On the first main surface side of the n−-surface region, a plurality of p-guard ring regions are formed to be separated from each other. A field plate electrode is connected electrically to the outermost p-guard ring region among the p-guard ring regions. A channel stopper electrode is connected electrically to an outermost peripheral p-region of the peripheral region.
摘要:
A cationic graft-copolymer for a drug delivery system comprising a unit derived from a having a hydroxyl groups, namely, a cationic polysaccharide of the following formula (1) (C6H7O2(OH)3-a (OX)a)xH2O (1) and a unit derived from a polymerizable olefin compound of the following formula (2) (a, x, X, R4, R5, R6, and R7 are defined in claim 1-8); a process for preparing the same and a transfection reagent made therefrom.
摘要:
A superjunction semiconductor device is disclosed which has, in the active section, a first alternating-conductivity-type layer which makes a current flow in the ON-state of the device and sustains a bias voltage in the OFF-state of the device. There is a second alternating-conductivity-type layer in a edge-termination section surrounding the active section. The width of a region of a second conductivity type in the second alternating-conductivity-type layer becomes narrower at a predetermined rate from the edge on the active section side toward the edge of the edge termination section. The superjunction semiconductor device facilitates manufacturing the edge-termination section which exhibits a high breakdown voltage and a high reliability for breakdown voltage through a process that exhibits a high mass-productivity.
摘要:
A semiconductor device has an active portion having at least one well region in a semiconductor layer, and a breakdown voltage maintaining structure surrounding the active portion. The maintaining structure includes a conductor layer over each of a plurality of guard rings with an insulating film interposed in between and connected to the respective guard ring. An inner side end portion of each conductor layer projects over the immediate adjacent inner side guard ring. The impurity concentration of the guard rings is set between the impurity concentrations of the semiconductor layer and the well regions. A field plate can extend over the innermost conductor layer with the insulating film interposed in between. The field plate is in contact with the outermost well region and is in contact with the first conductor layer. The outer side end of the field plate extends outwardly beyond an outer side end of the innermost conductor layer. With these arrangements, the guard rings can be shortened and the chip size can be reduced. Furthermore, the device can be made less susceptible to external charge.
摘要:
A cationic graft-copolymer for a non-viral gene delivery vector comprising a unit derived from a cationic derivative of a water-soluble linear polymers having a hydroxyl groups, namely, a cationic polysaccharide of the following formula (1) and the cationic derivative of polyvinylalcohol of the following formula (2) or the cationic derivative of the partial hydrolyzed polyvinylalcohol of the following formula (3) and a unit derived from a polymerizable olefin compound of the following formula (4) a process for preparing the same and a transfection reagent made therefrom.
摘要:
The superjunction semiconductor device includes a drain drift section, which includes a first alternating conductivity type layer formed of first n-type regions and first p-type regions arranged alternately. The device also includes a peripheral section around the drain drift section, which includes a second alternating conductivity type layer formed of second n-type regions and second p-type regions arranged alternately. The peripheral section further includes a third alternating conductivity type layer in its surface portion. The third alternating conductivity type layer is formed of third n-type regions and third p-type regions arranged alternately. At least the peripheral section is configured to improve the avalanche withstanding capability over the entire device.
摘要:
A semiconductor device includes an active region, an alternating conductivity type layer, and an insulation region surrounding the alternating conductivity type layer provided in a periphery section as a voltage withstanding section. The insulation region is made of an insulator with the critical electric field strength higher than that of the semiconductor and reaches an n+-drain layer on the bottom surface side of the device from a surface on the side on which a surface structure section is formed. In the alternating conductivity type layer, the width of the p-type partition region adjacent to the insulation region is made narrower than the width of the p-type partition region not adjacent to the insulation region to ensure a balanced state of charges at the end of the drift section made up of the alternating conductivity type layer. A high breakdown voltage is ensured with the length of the periphery section shortened.
摘要:
In a trench super junction semiconductor element having a parallel p-n junction layer 14 with n-drift regions 12 and p-partition regions 13, both extending in a depth direction, being alternately joined, a part 20 in a shape of a three-dimensional curved surface in the end portion of each of trenches is formed in a p-partition region 13. A section in the p-partition region 13 surrounding the part 20 in a shape of a three-dimensional curved surface of the end portion of each of the trenches is made as a p+-region 21 in which an impurity concentration is higher than that in a section thereunder so that an electric field is increased at a boundary between the p+-region 21 and the n-drift region 12, thereby lessening electric field concentration to the part 20 in a shape of a three-dimensional curved surface of the end portion of the trench. Moreover, the section in the p-partition region 13 surrounding the part 20 in a shape of a three-dimensional curved surface in the end portion of the trench can be formed wider than the section thereunder. This inhibits lowering in a breakdown voltage and, along with this, increases reliability of a gate insulator film.
摘要:
A lateral semiconductor device includes an alternating conductivity type layer for providing a first semiconductor current path in the ON-state of the device and for being depleted in the OFF-state of the device, that has an improved structure for realizing a high breakdown voltage in the curved sections of the alternating conductivity type layer.
摘要:
A semiconductor device facilitates obtaining a higher breakdown voltage in the portion of the semiconductor chip around the drain drift region and improving the avalanche withstanding capability thereof. A vertical MOSFET according to the invention includes a drain layer; a drain drift region on drain layer, drain drift region including a first alternating conductivity type layer; a breakdown withstanding region (the peripheral region of the semiconductor chip) on drain layer and around drain drift region, breakdown withstanding region providing substantially no current path in the ON-state of the MOSFET, breakdown withstanding region being depleted in the OFF-state of the MOSFET, breakdown withstanding region including a second alternating conductivity type layer, and an under region below a gate pad, and the under region including a third alternating conductivity type layer.