In a general aspect, a power semiconductor device can include a first trench shield electrode and a second trench shield electrode defined in a semiconductor region, the first and second trench shield electrodes each having a first portion disposed in an active region and a second portion disposed in a termination region. A trench of the first trench shield electrode and a trench of the second trench shield electrode can define a mesa of the semiconductor region therebetween. The device can further include an implant enrichment region disposed in the termination region, the implant enrichment region can have a plurality of segments, at least one of the segments being disposed in the mesa. The trench shield electrodes can be disposed between segments of the implant enrichment region.

Provided is a semiconductor device including a buffer region. Provided is a semiconductor device including: semiconductor substrate of a first conductivity type; a drift layer of the first conductivity type provided in the semiconductor substrate; and a buffer region of the first conductivity type provided in the drift layer, the buffer region having a plurality of peaks of a doping concentration, wherein the buffer region has: a first peak which has a predetermined doping concentration, and is provided the closest to a back surface of the semiconductor substrate among the plurality of peaks; and a high-concentration peak which has a higher doping concentration than the first peak, and is provided closer to an upper surface of the semiconductor substrate than the first peak is.

A plurality of trench stripes are disposed in parallel in an epitaxial layer on a drain and extends from a top region to a bottom region of a first surface of the semiconductor. A first polysilicon layer is in each of the trench stripes. The first polysilicon layer extends between the drain and the first surface proximal to the top region and the bottom region, and between the drain and a level below the first surface in a middle region between the top region and the bottom region. A second polysilicon layer is over the first polysilicon layer in the middle region, wherein the first poly silicon layer forms a shield, and the second polysilicon layer forms a gate. A source is in a silicon mesa stripe surrounding the first trench stripe.

A nitride power transistor comprises: a silicon substrate comprising a differently doped semiconductor composite structure for forming a space charge depletion region; and a nitride epitaxial layer located on the silicon substrate. With introduction of a differently doped semiconductor composite structure for forming a space charge depletion region inside a silicon substrate of a nitride power transistor, the nitride power transistor is capable of withstanding a relatively high external voltage, and thus a breakdown voltage of the device is improved.

The embodiments of the present invention disclose a high electron mobility transistor, comprising: a substrate; a channel layer located on the substrate; a barrier layer located on the channel layer; a source electrode, a drain electrode, and a schottky gate electrode located between the source electrode and the drain electrode, all located on the barrier layer; and at least one semiconductor field ring located on the barrier layer and between the schottky gate electrode and the drain electrode. In the embodiments of the present invention, a concentration of two-dimensional electron gas at an interface between a barrier layer and a channel layer can be adjusted. Therefore, the concentration effect of the electric field at an edge of a gate is effectively improved, and the breakdown voltage of high electron mobility transistors is increased.

A semiconductor structure including a substrate, a first dielectric layer, a first conductive layer, a positioning part, two spacers, and a second conductive layer is provided. The substrate has a first trench. The first dielectric layer is disposed on a surface of the first trench. The first conductive layer is filled in the first trench and located on the first dielectric layer. The positioning part is disposed on the substrate and has a first opening. The first opening exposes the first trench. The spacers are disposed on two sidewalls of the first opening and expose the first conductive layer. The second conductive layer is filled in the first opening and electrically connected to the first conductive layer. The semiconductor structure can prevent the generation of leakage current while maintaining a high breakdown voltage.

Apparatus and methods for providing variable regulated voltages are disclosed. Variable voltage control elements can adjust a regulated voltage provided by a single voltage regulator, thereby providing a variable regulated voltage. The regulated voltage can be used in a variety of applications, for example, as a bias voltage for a power amplifier.

In a general aspect, a power semiconductor device can include a first trench shield electrode and a second trench shield electrode defined in a semiconductor region, the first and second trench shield electrodes each having a first portion disposed in an active region and a second portion disposed in a termination region. A trench of the first trench shield electrode and a trench of the second trench shield electrode can define a mesa of the semiconductor region therebetween. The device can further include an implant enrichment region disposed in the termination region, the implant enrichment region can be intersected by the first trench shield electrode and the second trench shield electrode, and can have a portion disposed in the mesa of the semiconductor region, the portion extending from the trench of the first trench shield electrode to the trench of the second trench shield electrode.

A method includes: forming a barrier layer in a substrate; depositing a first dielectric layer over the substrate; forming a patterned mask layer over the first dielectric layer;

patterning the first dielectric layer into a first sublayer of a gate dielectric layer;

converting at least part of the patterned mask layer into a second sublayer of the gate dielectric layer; depositing a second dielectric layer adjacent to the first and second sublayers to serve as a third sublayer of the gate dielectric layer; and depositing a gate electrode over the gate dielectric layer.

A method includes forming a first isolation region in a substrate, wherein a top surface of the first isolation region is lower than a top surface of the substrate, depositing a gate electrode layer over the substrate and patterning the gate electrode layer to form a first gate electrode region and a second gate electrode region, wherein the second gate electrode region is vertically aligned with the first isolation region and the first gate electrode region is immediately adjacent to the second gate electrode region.