Methods are provided for fabricating a HEMT (high-electron-mobility transistor) that involve sequential epitaxial growth of III-nitride channel and barrier layers, followed by epitaxial regrowth of further III-nitride material through a window in a mask layer. In examples, the regrowth takes place over exposed portions of the channel layer in the source and drain regions of the device, and the regrown material has a composition different from the barrier layer. In other examples, the regrowth takes place on the barrier layer, only in the access region or regions. Devices made according to the disclosed methods are also provided.

The disclosure is directed to a high-electron mobility transistor that includes a SiC substrate layer, a GaN buffer layer arranged on the SiC substrate layer, and a p-type material layer having a length parallel to a surface of the SiC substrate layer over which the GaN buffer layer is provided. The p-type material layer is provided in one of the following: the SiC substrate layer and a first layer arranged on the SiC substrate layer. A method of making the high-electron mobility transistor is also disclosed.

Semiconductor structures with reduced parasitic capacitance between interconnects and ground, for example, are described. An example method for making a semiconductor structure includes forming a trench in an interconnect area of a substrate between first and second device areas in the semiconductor structure, forming a low dielectric constant material region in the trench, forming a III-nitride material layer over the substrate and over the low dielectric constant material region in the trench, forming a first device in the III-nitride material layer in the first device area, forming a second device in the III-nitride material layer in the second device area, and forming an interconnect over the low dielectric constant material region, the interconnect comprising a continuous conductive metal interconnect from the first device area, over the low dielectric constant material region, and to the second device area.

A microelectronic device includes a lower buffer layer of III-N semiconductor material formed over a silicon substrate. A screen layer having free charge carriers is formed over the lower buffer layer. The microelectronic device may include an upper buffer layer of III-N semiconductor material formed over the screen layer. A gallium nitride field effect transistor (GaN FET) is formed over the screen layer. The GaN FET has a two-dimensional electron gas (2DEG) layer directly over at least a portion of the screen layer. The screen layer may include a doped layer of III-N semiconductor material, or a buried barrier layer with 2DEG layers in the lower and upper buffer layers. The screen layer is electrically connected to a current node, that is, a source node or a drain node, of the GaN FET.

A semiconductor device includes a layer of a first semiconducting material, where the first semiconducting material is epitaxially grown to have a crystal structure of a first substrate. The semiconductor device further includes a layer of a second semiconducting material disposed adjacent to the layer of the first semiconducting material to form a heterojunction with the layer of the first semiconducting material. The semiconductor device further includes a first component that is electrically coupled to the heterojunction, and a second substrate that is bonded to the layer of the first semiconducting material.

In accordance with an embodiment, a semiconductor component includes a plurality of layers of compound semiconductor material over a body of semiconductor material and first and second filled trenches extending into the plurality of layers of compound semiconductor material. The first trench has first and second sidewalls and a floor and a first dielectric liner over the first and second sidewalls and the second trench has first and second sidewalls and a floor and second dielectric liner over the first and second sidewalls of the second trench.

A wafer includes a semiconductor substrate. The semiconductor substrate includes a plurality of first doped regions and a plurality of second doped regions. The first doped regions and the second doped regions are located on a first surface of the semiconductor substrate. The second doped regions contact the first doped regions. The first doped regions and the second doped regions are alternately arranged. Both of the first doped regions and the second doped regions include a plurality of N-type dopants. The doping concentration of the N-type dopants in each of the first doped regions is not greater than the doping concentration of the N-type dopants in each of the second doped regions.

A compound semiconductor field effect transistor may include a channel layer. The compound semiconductor transistor may also include a multi-layer epitaxial barrier layer on the channel layer. The channel layer may be on a doped buffer layer or on a first un-doped buffer layer. The compound semiconductor field effect transistor may further include a gate. The gate may be on a first tier of the multi-layer epitaxial barrier layer, and through a space between portions of a second tier of the multi-layer epitaxial barrier layer.

Semiconductor structures and fabrication methods are provided. An exemplary fabrication method includes providing a semiconductor substrate having at least one diode region; forming at least one first fin on the semiconductor substrate in the diode region; forming a first doped layer containing a first type of doping ions having a first conductivity in the first fin; and forming a second doped layer doped containing a second type of doping ions having a second conductivity opposite to the first conductivity on the first doped layer. A size of an interface between the first doped layer and the second doped layer along a width direction of the first fin is greater than a width of the first fin.

A semiconductor device is provided that comprises a base structure, a first channel layer overlying the base structure, a second channel layer overlying the first channel layer, and first, second, and third ohmic contacts overlying the second channel layer. The semiconductor device further comprises a metal-semiconductor heterodimension field effect transistor that is formed between the first and second ohmic contacts, the metal-semiconductor heterodimension field effect transistor including a first gate formed through the first and second channel layers. The semiconductor device yet further comprises a high electron mobility transistor formed between the second and third ohmic contacts, the high electron mobility transistor including a second gate formed through the second channel layer without extending through the first channel layer.