A method of forming a device is disclosed. A substrate defined with a device region is provided. A gate having a gate electrode, first and second gate dielectric layers is formed in a trench. The trench has an upper trench portion and a lower trench portion. A field plate is formed in the trench. First and second diffusion regions are formed. The gate is displaced from the second diffusion region.

A semiconductor power device comprises a plurality of power transistor cells each having a trenched gate disposed in a gate trench wherein the trenched gate comprising a shielding bottom electrode disposed in a bottom portion of the gate trench electrically insulated from a top gate electrode disposed in a top portion of the gate trench by an inter-electrode insulation layer. At least one of the transistor cells includes the shielding bottom electrode functioning as a source-connecting shielding bottom electrode electrically connected to a source electrode of the semiconductor power device and at least one of the transistor cells having the shielding bottom electrode functioning as a gate-connecting shielding bottom electrode electrically connected to a gate metal of the semiconductor power device.

A method of manufacturing a structure in a semiconductor body comprises forming a first mask above a first surface of the semiconductor body. The first mask comprises an opening surrounding a first portion of the first mask, thereby separating the first portion and a second portion of the first mask. The semiconductor body is processed through the opening at the first surface. The opening is increased by removing at least part of the first mask in the first portion while maintaining the first mask in the second portion. The semiconductor body is further processed through the opening at the first surface.

A semiconductor device is provided that includes a transistor in a semiconductor body having a main surface. The transistor includes a source region, a drain region, a body region, a drift zone, and a gate electrode at the body region. The body region and the drift zone are disposed along a first direction between the source region and the drain region. The first direction is parallel to the main surface. The semiconductor device further includes a field plate disposed in field plate trenches extending along the first direction in the drift zone, and a field dielectric layer between the field plate and the drift zone. A thickness of the field dielectric layer gradually increases along the first direction from a portion adjacent to the source region to a portion adjacent to the drain region.

A semiconductor device is provided. The semiconductor device includes a semiconductor substrate, a P-well and an N-well disposed in the semiconductor substrate, a source disposed in the N-well and a drain disposed in the P-well, a shallow trench isolation (STI) structure disposed in the P-well, a gate structure disposed on the semiconductor substrate, wherein a portion of the gate structure extends into the semiconductor substrate and is disposed in a location corresponding to the STI structure.

In accordance with an embodiment, a cascode connected semiconductor component and a method for manufacturing the cascode connected semiconductor component are provided. The cascode connected semiconductor component has a pair of silicon based transistors, each having a body region, a gate region over the body region, a source region and a drain. The source regions of a first and second silicon based transistor are electrically connected together and the drain regions of the first and second silicon based transistors are electrically connected together. The gate region of the second silicon based transistor is connected to the drain regions of the first and second silicon based transistors. The body region of the second silicon based transistor has a dopant concentration that is greater than the dopant concentration of the first silicon based transistor. A gallium nitride based transistor has a source region coupled to the first and second silicon based transistor.

A semiconductor device includes: a first semiconductor layer which is formed over a substrate and is formed from a nitride semiconductor; a second semiconductor layer which is formed over the first semiconductor layer and is formed from a nitride semiconductor; a third semiconductor layer which is formed over the second semiconductor layer and is formed from a nitride semiconductor; a source electrode and a drain electrode which are formed over the third semiconductor layer; an opening which is formed in the second semiconductor layer and the third semiconductor layer between the source electrode and the drain electrode; an insulating layer which is formed on a side surface and a bottom surface of the opening; and a gate electrode which is formed in the opening through the insulating layer.

A process for fabricating a semiconductor structure is disclosed. The process includes: forming an isolation trench in a substrate; forming a trench fill layer to at least fill the isolation trench in the substrate, the silicon oxide trench fill layer comprising a portion in contact with the substrate below an upper surface of the substrate; exposing a sidewall of the isolation trench and without exposing a bottom of the isolation trench in the substrate; and forming a gate structure over the substrate, wherein the gate structure contacts the sidewall of the isolation trench.

A multi-layer semiconductor structure is disclosed for use in III-Nitride semiconductor devices, including a channel layer, a band-offset layer having a wider bandgap than the channel layer, a spacer layer having a narrower bandgap than the band-offset layer, and a cap layer comprising at least two sublayers. Each sublayer is selectively etchable with respect to sublayers immediately below and above, each sublayer comprises a III-N material Al.sub.xIn.sub.yGa.sub.zN in which 0x1, 0y1, and 0z1, at least one sublayer has a non-zero Ga content, and a sublayer immediately above the spacer layer has a wider bandgap than the spacer layer. Also described are methods for fabricating such semiconductor structures, with gate and/or ohmic recesses formed by selectively removing adjacent layers or sublayers. The performance of resulting devices is improved, while providing design flexibility to reduce production cost and circuit footprint.

A method of fabricating a semiconductor device is disclosed. A semiconductor substrate is provided. A high-voltage well and a pre-recessed region are formed in the semiconductor substrate. A drift region is formed in the high-voltage well. A recessed channel region is formed adjacent to the drift region. A heavily doped drain region is formed in the drift region and spaced apart from the recessed channel region. An isolation structure is formed between the recessed channel region and the heavily doped drain region in the drift region. The isolation structure overlaps with the pre-recessed region. A buried gate dielectric layer is formed on the recessed channel region. A top surface of the buried gate dielectric layer is lower than a top surface of the heavily doped drain region. A gate is formed on the buried gate dielectric layer.