A semiconductor structure includes a first device and a second device. The first device has a first surface. The first device includes a first active region defined by a first material system. The second device has a second surface. The second surface is coplanar with the first surface. The second device includes a second active region defined by a second material system. The second material system is different from the first material system.

Radiation hardened NMOS devices suitable for application in NMOS, CMOS, or BiCMOS integrated circuits, and methods for fabricating them. A device includes a p-type silicon substrate, a field oxide surrounding a moat region on the substrate tapering through a Bird's Beak region to a gate oxide within the moat region, a heavily-doped p-type guard region underlying at least a portion of the Bird's Beak region and terminating at the inner edge of the Bird's Beak region, a gate included in the moat region, and n-type source and drain regions spaced by a gap from the inner edge of the Bird's Beak and guard regions. A variation of minor alterations to the conventional moat and n-type source/drain masks. The resulting devices have improved radiation tolerance while having a high breakdown voltage and minimal impact on circuit density.

According to an embodiment, a bipolar transistor is disclosed for Electrostatic discharge (ESD) management in integrated circuits. The bipolar transistor enables vertical current flow in a bipolar transistor cell configured for ESD protection. The bipolar transistor includes a selectively embedded P-type floating buried layer (PBL). The floating P-region is added in a standard NPN cell. During an ESD event, the base of the bipolar transistor extends to the floating P-region with a very small amount of current. The PBL layer can provide more holes to support the current resulting in decreased holding voltage of the bipolar transistor. With the selective addition of floating P-region, the current scalability of the bipolar transistor at longer pulse widths can be significantly improved.

Embodiments include methods of forming a semiconductor device having a first conductivity type, an isolation structure (including a sinker region and a buried layer), an active device within area of the substrate contained by the isolation structure, and a diode circuit. The buried layer is positioned below the top substrate surface, and has a second conductivity type. The sinker region extends between the top substrate surface and the buried layer, and has the second conductivity type. The active device includes a source region of the first conductivity type, and the diode circuit is connected between the isolation structure and the source region. The diode circuit may include one or more Schottky diodes and/or PN junction diodes. In further embodiments, the diode circuit may include one or more resistive networks in series and/or parallel with the Schottky and/or PN diode(s).

A transient voltage suppressor can include: a semiconductor substrate; a first buried layer of a first type formed in and on the semiconductor substrate; a second buried layer of a second type formed in a first region of the first buried layer; a first epitaxial region of the second type formed on the second buried layer and a second epitaxial region of the first type formed on a second region of the first buried layer; a first doped region of the first type formed in the first epitaxial region and a second doped region of the second type formed in the second epitaxial region; a conductive channel extending from a surface of the second epitaxial region into the first buried layer; and a first electrode connected to the conductive channel, a second electrode connected to the first doped region, and a third electrode connected to the second doped region.

A semiconductor device according to an embodiment includes a first semiconductor layer of a first conductivity type, a second semiconductor layer of a second conductivity type, a third semiconductor layer of the first conductivity type, a fourth semiconductor layer of the second conductivity type, a first electrode connected to the second semiconductor layer and the fourth semiconductor layer, a second electrode facing the second semiconductor layer with an insulating film interposed, a fifth semiconductor layer of the second conductivity type, a sixth semiconductor layer of the first conductivity type, a seventh semiconductor layer of the second conductivity type, a third electrode connected to the fifth semiconductor layer and the seventh semiconductor layer, and a fourth electrode facing the fifth semiconductor layer with an insulating film interposed.

According to one embodiment, the insulating film is provided between the anode region and the cathode region in the surface of the second semiconductor region. The third semiconductor region is provided inside the second semiconductor region. The third semiconductor region covers a corner of the insulating film on the anode region side. The first electrode contacts the anode region and the third semiconductor region. The second electrode contacts the cathode region. The third electrode is provided on the insulating film and positioned on a p-n junction between the second semiconductor region and the third semiconductor region.

The invention provides a semiconductor device layout structure disposed in an active region. The semiconductor device layout structure includes a first well region having a first conduction type. A second well region having a second conduction type opposite the first conduction type is disposed adjacent to and enclosing the first well region. A first doped region having the second conduction type is disposed within the first well region. A second doped region having the second conduction type is disposed within the first well region. The second doped region is separated from and surrounds the first doped region. A third doped region having the second conduction type is disposed within the second well region.

A current aperture vertical electron transistor (CAVET) with ammonia (NH.sub.3) based molecular beam epitaxy (MBE) grown p-type Gallium Nitride (p-GaN) as a current blocking layer (CBL). Specifically, the CAVET features an active buried Magnesium (Mg) doped GaN layer for current blocking purposes. This structure is very advantageous for high power switching applications and for any device that requires a buried active p-GaN layer for its functionality.

A manufacturable and economically viable edge termination structure allows a semiconductor device to withstand a very high reverse blocking voltage (for example, 8500 volts) without suffering breakdown. A P type peripheral aluminum diffusion region extends around the bottom periphery of a thick die. The peripheral aluminum diffusion region extends upward from the bottom surface of the die, extending into N type bulk silicon. A deep peripheral trench extends around the upper periphery of the die. The deep trench extends from the topside of the die down toward the peripheral aluminum diffusion region. A P type sidewall doped region extends laterally inward from the inner sidewall of the trench, and extends laterally outward from the outer sidewall of the trench. The P type sidewall doped region joins with the P type peripheral aluminum diffusion region, thereby forming a separation edge diffusion structure that surrounds the active area of the die.