A varactor transistor includes a semiconductor fin having a first conductivity type, a plurality of gate structures separated from each other and surrounding a portion of the semiconductor fin. The plurality of gates structures include a dummy gate structure on an edge of the semiconductor fin, and a first gate structure spaced apart from the dummy gate structure. The dummy gate structure and the gate structure each include a gate insulator layer on a surface portion of the semiconductor fin, a gate on the gate insulator layer, and a spacer on the gate. The varactor transistor also includes a raised source/drain region on the semiconductor fin and between the dummy gate structure and the first gate structure, the raised source/drain region and the gate of the dummy gate structure being electrically connected to a same potential.

A gate stack structure for a MOS varactor includes a substrate including a channel region, a high-k dielectric layer on the channel region of the substrate, a P-type work function adjustment layer on the high-k dielectric layer, an N-type work function adjustment layer on the P-type work function adjustment layer, and a metal gate on the N-type work function adjustment layer. The P-type work function adjustment layer includes a first portion and a second portion laterally adjacent to each other, the first portion having a thickness greater than a thickness of the second portion. The gate stack structure in the MOS varactor can increase the tuning range of the MOS varactor.

A varactor structure includes a substrate. A first and second gate structure are disposed on the substrate. The first and second gate structures each include a base portion and a plurality of line portions connected thereto. The line portions of each of the first and second gate structures is alternately arranged. A meander diffusion region is formed in the substrate and surrounds the line portions. A first set of contact plugs is planned with at least two columns or rows and disposed on the base portions of the first and second gate structures. A second set of contact plugs is planned with at least two columns or rows and disposed on the meander diffusion region. A first conductive layer is disposed on a top end of the first set of contact plugs. A second conductive layer is disposed on a top end of the second set of contact plugs.

A semiconductor device includes a first and a second switching element, a first and a second conductive member, and a capacitor. The first switching element has a first element obverse surface and a first element reverse surface facing away from each other in a first direction. The second switching element has a second element obverse surface and a second element reverse surface facing away from each other in the first direction. The first and second conductive members are spaced apart in a second direction orthogonal to the first direction. The capacitor has a first and a second connection terminal. The first and second switching elements are connected in series, forming a bridge. The first and second connection terminals are electrically connected to opposite ends of the bridge. The capacitor and the first switching element are on the first conductive member, the second switching element on the second conductive member.

A low noise device includes an isolation feature in a substrate. The low noise device further includes a gate stack over a channel in the substrate. The gate stack includes a gate dielectric layer extending over a portion of the isolation feature, and a gate electrode over the gate dielectric layer. The low noise device further includes a charge trapping reducing structure adjacent to the isolation feature. The charge trapping reducing structure is configured to reduce a number of charge carriers adjacent an interface between the isolation feature and the channel.

A varactor structure includes a substrate. A first and second gate structure are disposed on the substrate. The first and second gate structures each include a base portion and a plurality of line portions connected thereto. The line portions of each of the first and second gate structures is alternately arranged. A meander diffusion region is formed in the substrate and surrounds the line portions. A first set of contact plugs is planned with at least two columns or rows and disposed on the base portions of the first and second gate structures. A second set of contact plugs is planned with at least two columns or rows and disposed on the meander diffusion region. A first conductive layer is disposed on a top end of the first set of contact plugs. A second conductive layer is disposed on a top end of the second set of contact plugs.

Reliability of an electrical test of a semiconductor wafer is improved. A method of manufacturing a semiconductor device includes a step of performing an electrical test of a semiconductor element by allowing contact portions (tips) of a force terminal (contact terminal) and a sense terminal (contact terminal) held by a probe card (first card) to come into contact with an electrode terminal of a semiconductor wafer. In the step of performing the electrical test, the contact portions of the force terminal and the sense terminal move in a direction away from each other after coming into contact with the first electrode terminal.

A capacitor structure includes a semiconductor substrate, a first vertical diffusion plate in the semiconductor substrate, a first STI structure in the semiconductor substrate and surrounding the first vertical diffusion plate, a second vertical diffusion plate in the semiconductor substrate and surrounding the first STI structure, and an ion well in the semiconductor substrate. The ion well is disposed directly under the first vertical diffusion plate, the first STI structure and the second vertical diffusion plate. The second vertical diffusion plate is electrically coupled to an anode of the capacitor structure. The first vertical diffusion plate is electrically coupled to a cathode of the capacitor structure.

At least one bipolar transistor and at least one variable capacitance diode are jointly produced by a method on a common substrate.

A pyroelectric device having a substrate and a first electrode overlying at least a portion of the substrate. A plurality of spaced apart nanometer sized pyroelectric elements are electrically connected to and extending outwardly from the first electrode so that each element forms a single domain. A dielectric material is deposited in the space between the individual elements and a second electrode spaced apart from said first electrode is electrically connected to said pyroelectric elements.