The present disclosure relates to a semiconductor device including a first high electron mobility transistor (HEMT) device disposed within a semiconductor structure and having a first source, a first drain, and a first gate; a second HEMT device disposed within the semiconductor structure and having a second source, a second drain, and a second gate, the second source coupled to the first drain; and a diode-connected transistor device disposed within the semiconductor structure and comprising a third source, a third gate, and a third drain, the third drain coupled to the second gate.

An embodiment system comprises a physical unclonable function device, wherein the device comprises a first assembly of non-volatile memory cells each having a selection transistor embedded in a semiconductor substrate and a depletion-type state transistor having a control gate and a floating gate that are electrically connected, the state transistors having respective effective threshold voltages belonging to a common random distribution, and a processing circuit configured to deliver, to an output interface of the device, a group of output data based on a reading of the effective threshold voltages of the state transistors of the memory cells of the first assembly.

A semiconductor device containing an enhancement mode GaN FET on a III-N layer stack includes a low-doped GaN layer, a barrier layer including aluminum over the low-doped GaN layer, a stressor layer including indium over the barrier layer, and a cap layer including aluminum over the stressor layer. A gate recess extends through the cap layer and the stressor layer, but not through the barrier layer. The semiconductor device is formed by forming the barrier layer with a high temperature MOCVD process, forming the stressor layer with a low temperature MOCVD process and forming the cap layer with a low temperature MOCVD process. The gate recess is formed by a two-step etch process including a first etch step to remove the cap layer, and a second etch step to remove the stressor layer.

Apparatus and circuits with dual polarization transistors and methods of fabricating the same are disclosed. In one example, a semiconductor structure is disclosed. The semiconductor structure includes: a substrate; an active layer that is formed over the substrate and comprises a first active portion having a first thickness and a second active portion having a second thickness; a first transistor comprising a first source region, a first drain region, and a first gate structure formed over the first active portion and between the first source region and the first drain region; and a second transistor comprising a second source region, a second drain region, and a second gate structure formed over the second active portion and between the second source region and the second drain region, wherein the first thickness is different from the second thickness.

A semiconductor integrated circuit includes: a semiconductor base body of a first conductivity-type; a bottom surface electrode to which a first potential is applied, the bottom surface electrode being provided on a bottom surface of the semiconductor base body; a first well of a second conductivity-type to which a second potential lower than the first potential is applied, the first well being provided on a top surface side of the semiconductor base body; a second well of the first conductivity-type provided in the first well; and an edge structure provided in the first well and configured to supply a third potential higher than the second potential to the second well.

The present disclosure describes a composite device including first field effect transistor (FET) device and second FET device. First FET device includes first drain, first source, first gate and shielding terminal. First FET device is made of wide-bandgap semiconductor material. Second FET device includes second drain, second source, and second gate. First and second FET devices are electrically connected in cascode configuration for providing a capacitive path between drain and gate terminals of composite device such that current flowing through gate terminal controls slew rate of drain voltage appearing at drain terminal. Cascode configuration includes an electrical connection of first drain to drain terminal, an electrical connection of first source to second drain, an electrical connection of second gate to first gate and gate terminal, an electrical connection of shielding terminal to second source, and an electrical connection of second source to source terminal of composite device.

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.

We disclose herein a depletion mode III-nitride semiconductor based heterojunction device, comprising: a substrate; a III-nitride semiconductor region formed over the substrate, wherein the III-nitride semiconductor region comprises a heterojunction comprising at least one two-dimensional carrier gas of second conductivity type; a first terminal operatively connected to the III-nitride semiconductor region; a second terminal laterally spaced from the first terminal in a first dimension and operatively connected to the III-nitride semiconductor region; at least two highly doped semiconductor regions of a first conductivity type formed over the III-nitride semiconductor region, the at least two highly doped semiconductor regions being formed between the first terminal and the second terminal; and a gate terminal formed over the at least two highly doped semiconductor regions; wherein the at least two highly doped semiconductor regions are spaced from each other in a second dimension.

A semiconductor device including: a substrate in which a first transistor region and a second transistor region are provided; a first channel layer in which a carrier of a first conductivity type travels, the first channel layer being provided over the substrate in the first transistor region and including a compound semiconductor; a first impurity epitaxial layer of a second conductivity type that is provided over the substrate with the first channel layer interposed therebetween, is disposed in a first gate region in a central portion and outside the first gate region, and has a low concentration region in which an electric charge amount per unit length is small as compared to the first gate region; and a second channel layer in which a carrier of the second conductivity type travels, the second channel layer being provided over the substrate in the second transistor region and including a compound semiconductor.

Apparatus and circuits including transistors with different threshold voltages and methods of fabricating the same are disclosed. In one example, a semiconductor structure is disclosed. The semiconductor structure includes: a substrate; an active layer that is formed over the substrate and comprises a plurality of active portions; a polarization modulation layer comprising a plurality of polarization modulation portions each of which is disposed on a corresponding one of the plurality of active portions; and a plurality of transistors each of which comprises a source region, a drain region, and a gate structure formed on a corresponding one of the plurality of polarization modulation portions. The transistors have at least three different threshold voltages.