IC structures with air gap insulation in place of gate spacers are disclosed. An example IC structure includes a transistor comprising a channel region and a source or drain (S/D) region, a gate structure coupled to the channel region and comprising a gate electrode material and a first electrically conductive material, a S/D contact structure coupled to the S/D region and comprising a second electrically conductive material, a gap between the gate structure and the S/D contact structure, and a liner material on at least a portion of a sidewall of the gap, the liner material comprising aluminum and oxygen.

Tunneling field effect transistors (TFETs) for CMOS architectures and approaches to fabricating N-type and P-type TFETs are described. For example, a tunneling field effect transistor (TFET) includes a homojunction active region disposed above a substrate. The homojunction active region includes a relaxed Ge or GeSn body having an undoped channel region therein. The homojunction active region also includes doped source and drain regions disposed in the relaxed Ge or GeSn body, on either side of the channel region. The TFET also includes a gate stack disposed on the channel region, between the source and drain regions. The gate stack includes a gate dielectric portion and gate electrode portion.

An embodiment includes a heterojunction tunneling field effect transistor including a source, a channel, and a drain; wherein (a) the channel includes a major axis, corresponding to channel length, and a minor axis that corresponds to channel width and is orthogonal to the major axis; (b) the channel length is less than 10 nm long; (c) the source is doped with a first polarity and has a first conduction band; (d) the drain is doped with a second polarity, which is opposite the first polarity, and the drain has a second conduction band with higher energy than the first conduction band. Other embodiments are described herein.

A method of making a semiconductor device includes forming a nanosheet stack including a first layer and a second layer; patterning a gate stack on the nanosheet stack; forming a first spacer along a sidewall of the gate stack; removing an endwall portion of the nanosheet stack that extends beyond the first spacer such that a portion of the second layer is exposed from a sidewall of the first spacer; depositing a second spacer along a sidewall of the first spacer; recessing the substrate beneath the second spacer to form an isolation region; depositing an oxide on the gate stack and within the isolation region and partially recessing the oxide; removing a portion of the second spacer such that the portion of the second layer is exposed; and growing an epitaxial layer on the portion of the second layer that is exposed to form a source/drain over the isolation region.

A semiconductor device includes a first type region including a first conductivity type and a second type region including a second conductivity type. The semiconductor device includes a channel region extending between the first type region and the second type region. The semiconductor device includes a gate electrode surrounding at least some of the channel region. A first gate edge of the gate electrode is separated a first distance from a first type region edge of the first type region and a second gate edge of the gate electrode is separated a second distance from a second type region edge of the second type region. The first distance is less than the second distance.

A semiconductor device includes at least one nanowire that is disposed over a substrate, extends to be spaced apart from the substrate, and includes a channel region, a gate that surrounds at least a part of the channel region, and a gate dielectric film that is disposed between the channel region and the gate. A source/drain region that contacts one end of the at least one nanowire is formed in a semiconductor layer that extends from the substrate to the one end of the at least one nanowire. Insulating spacers are formed between the substrate and the at least one nanowire. The insulating spacers are disposed between the gate and the source/drain region and are formed of a material that is different from a material of the gate dielectric film.

A semiconductor device includes a drain, a source, a gate electrode, and a nanowire between the source and drain. The nanowire has a first section with a first thickness and a second section with a second thickness greater than the first thickness. The second section is between the first section and at least one of the source or drain. The first nanowire includes a channel when a voltage is applied to the gate electrode.

A semiconductor device, such as an LED, includes a plurality of first conductivity type semiconductor nanowire cores located over a support, a continuous second conductivity type semiconductor layer extending over and around the cores, a plurality of interstitial voids located in the second conductivity type semiconductor layer and extending between the cores, and first electrode layer that contacts the second conductivity type semiconductor layer.

The disclosed technology generally relates to a semiconductor device, and more particularly to a gate all around (GAA) semiconductor device and a method for fabricating the same. In one aspect, a semiconductor device has a vertical stack of nanowires formed on a substrate, wherein the vertical stack of nanowires comprises an n-type nanowire and a p-type nanowire each extending in a longitudinal direction parallel to a main surface of the substrate. The n-type nanowire comprises a first material and the p-type nanowire comprises an inner part having two sides and an outer part at each side of the inner part in the longitudinal direction, wherein one or both of the two outer parts comprises a second material different from the first material. The n-type nanowire and the p-type nanowire each comprises a channel region electrically coupled to respective source and drain regions. The channel region of the p-type nanowire comprises the inner part. The device additionally includes a shared gate structure circumferentially surrounding the channel regions of the n-type and p-type nanowires.

A method for forming stacked, complementary transistors is disclosed. Selective deposition techniques are used to form a column having a lower portion that includes one type of semiconductor (e.g. germanium) and an upper portion of another type of semiconductor (e.g. indium arsenide. The lower portion of the column provides a channel region for a transistor of one type, while the upper column provides a channel region for a transistor of another type. This provides a complementary pair that occupies a minimum of integrated circuit surface area. The complementary transistors can be utilized in a variety of circuit configurations. Described are complementary transistors where the lower transistor is p-type and the upper transistor is n-type.