Raytheon Company

Other

Kiuchul Hwang

Brian D Schultz

John Logan

Adrian D Williams

Christos Thomidis

Michael G Adlerstein

Kezia Cheng

Christopher J MacDonald

Kamal Tabatabaie Alavi

Nicholas J Kolias

Robert E Leoni

Elsa K Tong

Amanda Kerr

Dale M Shaw

An Enhancement-Mode HEMT having a gate electrode with a doped, Group III-N material disposed between an electrically conductive gate electrode contact and a gate region of the Enhancement-Mode HEMT, such doped, Group III-N layer increasing resistivity of the Group III-N material to deplete the 2DEG under the gate at zero bias.

Semiconductor structure having both enhancement mode group III-N high electron mobility transistors and depletion mode group III-N high electron mobility transistors

A semiconductor device having a substrate, a pair of Group III-Nitride layers on the substrate forming: a heterojunction with a 2 Dimensional Electron Gas (2DEG) channel in a lower one of the pair of Group III-Nitride layers, a cap beryllium doped Group III-Nitride layer on the upper one of the pair of Group III-Nitride layers; and an electrical contact in Schottky contact with a portion of the cap beryllium doped, Group III-Nitride layer.

Depletion mode high electron mobility field effect transistor (HEMT) semiconductor device having beryllium doped Schottky contact layers

A method includes providing a single crystal substrate having a buffer layer on a surface of the substrate. The buffer layer provides a transition between the crystallographic lattice structure of the substrate and the crystallographic lattice structure of the semiconductor layer and has its resistivity increased by ion implanting a dopant into the buffer layer; and forming semiconductor layer on the ion implanted buffer layer. The semiconductor layer may be a wide bandgap semiconductor layer having a high electron mobility transistors formed therein.

Semiconductor material growth of a high resistivity nitride buffer layer using ion implantation

A Field Effect Transistor structure is provided having: a semi-insulating substrate; a semiconductor mesa structure disposed on the substrate and having a notch in an outer sidewall of the mesa structure; a source electrode disposed within the opposing sidewalls in ohmic contact with a source region of the mesa structure; a drain electrode disposed within the opposing sidewalls in ohmic contact with a drain region of the mesa; and a gate electrode, having an inner portion disposed between, and laterally of, the source electrode and the drain electrode and in Schottky contact with the mesa structure, extending longitudinally towards the notch and having outer portions extending beyond the mesa structure and over portions of the substrate outside of the mesa structure. In one embodiment, the mesa structure includes a pair of notches projecting inwardly towards each other and the inner portion of the gate extends longitudinally between the pair of notches.

Field effect transistor structure having notched mesa

A stack of layers providing an ohmic contact with the semiconductor, a lower metal layer of the stack is disposed in direct contact with the semiconductor; and a radiation absorption control layer disposed over the lower layer for controlling an amount of the radiant energy to be absorbed in the radiation absorption control layer during exposure of the stack to the radiation during a process used to alloy the stack with the semiconductor to form the ohmic contact.

Method for controlling the amount of radiation having a predetermined wavelength to be absorbed by a structure disposed on a semiconductor

A semiconductor structure having a T-shaped electrode. The electrode has a top portion and a narrower stem portion extending from the top portion to a surface of a substrate. A solid dielectric layer has side portions juxtaposed and abutting sidewalls of a lower portion of the stem of electrode. A bottom surface of the top portion is spaced from an upper surface portion by a non-solid dielectric, such as air.

Semiconductor structures having T-shaped electrodes

A semiconductor structure having: a III-V substrate structure; an enhancement mode transistor device disposed in a first region of the structure; a depletion mode transistor device disposed in a laterally displaced second region of the structure; and a RF/microwave/milli-meter wave transistor device formed in a laterally displaced third region thereof.

Monolithic integrated circuit having enhancement mode/depletion mode field effect transistors and RF/RF/microwave/milli-meter wave milli-meter wave field effect transistors

A field effect transistor device and method, such device having source and drain electrodes in ohmic contact a semiconductor. A gate electrode-field plate structure is disposed between the source and drain electrodes. The gate electrode-field plate structure comprises: a dielectric; a first metal in Schottky contact the semiconductor; and a second metal. The second metal has: a first portion disposed over and electrically connected to a portion of the first metal; and a second portion, separated from a second portion of the first metal by a portion of the dielectric and extending beyond an edge of the first metal to an edge of the second metal. The edge of the first metal is further from the drain electrode than the edge of the second metal to provide a field-plate for the field effect transistor.

Semiconductor devices having improved field plates

A semiconductor structure a structure with an enhancement mode transistor device disposed in a first region and depletion mode transistor device disposed in a laterally displaced second region. The structure has a channel layer for the depletion mode and enhancement mode transistor devices. An enhancement mode transistor device InGaP etch stop/Schottky contact layer is disposed over the channel layer; a first layer different from InGaP disposed on the InGaP layer; a depletion mode transistor device etch stop layer is disposed on the first layer; and a second layer disposed on the depletion mode transistor device etch stop layer. The depletion mode transistor device has a gate recess passing through the second layer and the depletion mode transistor device etch stop layer and terminating in the first layer. The enhancement mode transistor device has a gate recess passing through the second layer, the depletion mode transistor device etch stop layer, the first layer, and terminating in the InGaP layer.

Method of fabrication of a field effect transistor with materialistically different two etch stop layers in an enhanced mode transistor and an depletion mode transistor

Growing community of inventors

Amherst, NH, United States of America

Kiuchul Hwang