Abb Schweiz Ag

Andrei Mihaila

Renato Minamisawa

Munaf Rahimo

Lars Knoll

Holger Bartolf

Friedhelm Bauer

Vinoth Sundaramoorthy

Liutauras Storasta

A method of manufacturing a semiconductor device is provided with: (a) providing a wide bandgap substrate product, (b) forming source regions by applying a first mask with a first and second mask layer and applying an n dopant, forming a well layer by removing such part of the first mask, which is arranged between the two source regions, and applying a p dopant, forming two channel regions by forming a third mask by performing an etching step, by which the first mask layer is farther removed at the openings than the second mask layer, and then removing the second mask layer, wherein the remaining first mask layer forms a third mask and applying a p dopant, wherein a well layer depth is at least as large as a channel layer depth, (c) after step (b) for forming a plug applying a fourth mask, which covers the source regions and the channel layers and applying a p fourth dopant to a greater depth than the well layer depth and with a higher doping concentration than the well layers.

Semiconductor device and method for manufacturing such a semiconductor device

A wide bandgap semiconductor device is comprising an (n&#x2212;) doped drift layer between a first main side and a second main side. On the first main side, n doped source regions are arranged which are laterally surrounded by p doped channel layers having a channel layer depth. P+ doped well layers having a well layer depth, which is at least as large as the channel layer depth is arranged at the bottom of the source regions. A p++ doped plug extends from a depth, which is at least as deep as the source layer depth and less deep than the well layer depth, to a plug depth, which is as least as deep as the well layer depth, and having a higher doping concentration than the well layers, is arranged between the source regions and well layers. On the first main side, an ohmic contact contacts as a first main electrode the source regions, the well layers and the plug.

Method for manufacturing a semiconductor device

A method of manufacturing a semiconductor device is provided with: (a) providing a wide bandgap substrate product, (b) for forming two channel layers applying a first mask and applying a p first dopant, for forming two source regions forming a second mask by applying a further layer on the lateral sides of the first mask and applying an n second dopant, for forming two well layers forming a third mask by removing such part of the second mask between the source regions and applying a p third dopant, wherein a well layer depth is at least as large as a channel layer depth, (c) after step (b) for forming a plug applying a fourth mask, which covers the source regions and the channel layers and applying a p fourth dopant to a greater depth than the well layer depth and with a higher doping concentration than the well layers; wherein the well layers surround the plug in the lateral direction and separate it from the two source regions.

A semiconductor power rectifier with increased surge current capability is described. A semiconductor layer includes a drift layer having a first conductivity type, at least one pilot region having a second conductivity type different from the first conductivity type, a plurality of stripe-shaped emitter regions having the second conductivity type, and a transition region having the second conductivity type, wherein the at least one pilot region has in any lateral direction parallel to the first main side a width of at least 200 &#x3bc;m and is formed adjacent to the first main side to form a first p-n junction with the drift layer, each emitter region is formed adjacent to the first main side form a second p-n junction with the drift layer, and the transition region is formed adjacent to the first main side to form a third p-n junction with the drift layer.

Junction barrier schottky diode with enhanced surge current capability

It is the object of the invention to provide a power semiconductor rectifier with a low on-state-voltage and high blocking capability. The object is attained by a power semiconductor rectifier comprising: a drift layer having a first conductivity type; and an electrode layer forming a Schottky contact with the drift layer, wherein the drift layer includes a base layer having a peak net doping concentration, below 1&#xb7;10cmand a barrier modulation layer which is in direct contact with the electrode layer to form at least a part of the Schottky contact, wherein a net doping concentration of the barrier modulation layer is in a range between 1&#xb7;10cmand 1&#xb7;10cmand wherein the barrier modulation layer has a layer thickness in a direction vertical to the interface between the electrode layer and the barrier modulation, layer of at least 1 nm and less than 0.2 &#x3bc;m.

Power semiconductor rectifier with controllable on-state voltage

A junction barrier Schottky rectifier with first and second drift layer sections, wherein a peak net doping concentration of the first section is at least two times lower than a minimum net doping concentration of the second section. For each emitter region the first section includes a layer which is in contact with the respective emitter region to form a pn-junction between the first section and the respective emitter region, wherein the thickness of this layer in a direction perpendicular to the interface between the first section and the respective emitter region is at least 0.1 &#x3bc;m. The JBS rectifier has a transition from unipolar to bipolar conduction mode at a lower forward bias due to lowering of electrostatic forces otherwise impairing the transport of electrons toward the emitter regions under forward bias conditions, and with reduced snap-back phenomenon.

Growing community of inventors

Baden, Switzerland

Andrei Mihaila