129 results about "Drain resistance" patented technology

A hetero-junction FET has an intermediate layer including n-type-impurity doped layer between an electron supply layer and an n-type cap layer. The intermediate layer cancels the polarized negative charge generated between the electron supply layer and the n-type cap layer by ionized positive charge, thereby reducing the barrier against the electrons and source/drain resistance.

A method of forming a FINFET CMOS device structure featuring an N channel device and a P channel device formed in the same SOI layer, has been developed. The method features formation of two parallel SOI fin type structures, followed by gate insulator growth on the sides of the SOI fin type structures, and definition of a conductive gate structure formed traversing the SOI fin type structures while interfacing the gate insulator layer. A doped insulator layer of a first conductivity type is formed on the exposed top surfaces of a first SOI fin type shape, while a second doped insulator layer of a second conductivity type is formed on the exposed top surfaces of the second SOI fin type shape. An anneal procedure results creation of a source/drain region of a first conductivity type in portions of the first SOI fin type shape underlying the first doped insulator layer, and creation of a source/drain region of a second conductivity type in portions of the second SOI fin type shape underlying the second doped insulator layer. Selective deposition of tungsten on exposed top surface of the source/drain regions is then employed to decrease source/drain resistance.

An integrated circuit structure includes a substrate; a channel layer over the substrate, wherein the channel layer is formed of a first III-V compound semiconductor material; a highly doped semiconductor layer over the channel layer; a gate dielectric penetrating through and contacting a sidewall of the highly doped semiconductor layer; and a gate electrode on a bottom portion of the gate dielectric. The gate dielectric includes a sidewall portion on a sidewall of the gate electrode.

Various methods of fabricating a silicide layer, and devices incorporating the same are provided. In one aspect, a method of fabricating a silicide layer on a substrate is provided. The method includes the steps of damaging the crystal structure of a portion of the substrate positioned beneath the spacer and depositing a layer of metal on the substrate. The metal layer and the substrate are heated to react the metal with the substrate and form the silicide layer, whereby a portion of the silicide layer extends laterally beneath the spacer. Any unreacted metal is removed. The method enables fabrication of silicide layers with substantial lateral encroachment into LDD structures, resulting in lower possible source-to-drain resistance and enhanced performance for transistors.

A MOS transistor having a T-shaped gate electrode and a method for fabricating the same are provided, wherein the MOS transistor includes a T-shaped gate electrode on a semiconductor substrate; an L-shaped lower spacer disposed at both sides of the gate electrode to cover a top surface of the semiconductor substrate; and low-, mid-, and high-concentration impurity regions formed in the semiconductor substrate of both sides of the gate electrode. The high-concentration impurity region is disposed in the semiconductor substrate next to the lower spacer and the mid-concentration impurity region is disposed between the high- and low-concentration impurity regions. A MOS transistor according to the present invention provides a decrease in a capacitance, a decrease in a channel length, and an increase in a cross-sectional area of the gate electrode. At the same time, the mid-concentration impurity region provides a decrease in a source/drain resistance R_sd.

The invention discloses a MOSFET (metal-oxide-semiconductor field effect transistor) which effectively lowers source-drain contact resistance in post grid process and a manufacturing method thereof. The MOSFET comprises a substrate, a grid stacking structure, formed by a grid medium layer and a grid metal layer, on the substrate, source-drain areas in substrate parts on two sides of the grid stacking structure, grid side walls on substrate parts on two sides of the grid stacking structure, interlevel dielectric on the substrate, a source-drain contact plug in the interlevel dielectric on the source-drain areas and metal silicide between the source-drain areas and the source-drain contact plug and is characterized in that the interface of the metal silicide and the source-drain areas is provided with an ion-doped dephlegmation area, and the grid medium layer is located below and on the side of the grid metal layer. By the MOSFET which effectively lowers source-drain contact resistance and the manufacturing method thereof and the ion-doped dephlegmation area disposed on the interface between the metal silicide and the source-drain areas, Schottky barrier height can be reduced effectively, and accordingly source-drain resistance is reduced greatly, and device performance is further improved.

An integrated circuit structure includes a substrate, and a channel over the substrate. The channel includes a first III-V compound semiconductor material formed of group III and group V elements. A gate structure is over the channel. A source/drain region is adjacent the channel and includes a group-IV region formed of a doped group-IV semiconductor material selected from the group consisting essentially of silicon, germanium, and combinations thereof. By re-growing silicon/germanium source/drain regions, the existing silicidation technique can be used to reduce the source/drain resistance and to improve drive currents of the resulting transistors. Buffer layers have the effect of smoothening the lattice constant transition between the channel of the transistor and the source/drain regions, resulting in a reduced defect density and reduced junction leakage currents.

A drain-extended MOS transistor in a semiconductor wafer (300) of a first conductivity type comprises a first well (315) of the first conductivity type, operable as the extension of the transistor drain (305) of the first conductivity type, and covered by a first insulator (312) having a first thickness, and further a second well (302) of the opposite conductivity type, intended to contain the transistor source (304) of the first conductivity type, and covered by a second insulator (311) thinner than said first insulator (312). First and second wells form a junction (330) that terminates (320, 321) at the second insulator. The first well has a region (360) in the proximity of the junction termination, which has a higher doping concentration than the remainder of the first well and extends not deeper than the first insulator thickness. Region (360) of higher doping concentration reduces the transistor drain resistance so that the drain current is increased to approximately twice the value it had without the higher doping concentration, while the transistor breakdown voltage remains determined by the (low) doping concentration of the remainder of first well (315).

This invention provides a semiconductor device in which an ESD protection circuit and a termination circuit can be realized with a small die area. A PMOS transistor having an ESD protection function is placed between a signal node on a line from an signal terminal to an input buffer and a supply voltage node. Furthermore, a voltage generator circuit is placed to supply a reference voltage to the gate of the PMOS transistor. By the reference voltage controlled by the voltage generator circuit, a source-drain resistance of the PMOS transistor is set. Thereby, the PMOS transistor can be made to function as a terminating resistor whose resistance can be set adaptively to a characteristic impedance of a transmission line, for example, connected to the signal terminal in addition to the ESD protection function.

A method for reducing the drain resistance of a drain-extended MOS transistor in a semiconductor wafer, while maintaining a high transistor breakdown voltage. The method provides a first well (502) of a first conductivity type, operable as the extension of the transistor drain (501) of the first conductivity type; portions of the well are covered by a first insulator (503) having a first thickness. A second well (504) of the opposite conductivity type is intended to contain the transistor source (506) of the first conductivity type; portions of the second well are covered by a second insulator (507) thinner than the first insulator. The first and second wells form a junction (505) that terminates at the second insulator (530a, 530b). The method deposits a photoresist layer (510) over the wafer, which is patterned by opening a window (510a) that extends from the drain to the junction termination. Next, ions (540) of the first conductivity type are implanted through the window into the first well; these said ions have an energy to limit the penetration depth (541) to the first insulator thickness, and a dose to create a well region (560) of high doping concentration adjacent to the junction termination (530a).

To provide a highly reliable semiconductor device. To provide a semiconductor device which prevents a defect and achieves miniaturization. An oxide semiconductor layer in which the thickness of a region serving as a source region or a drain region is larger than the thickness of a region serving as a channel formation region is formed in contact with an insulating layer including a trench. In a transistor including the oxide semiconductor layer, variation in threshold voltage, degradation of electric characteristics, and shift to normally on can be suppressed and source resistance or drain resistance can be reduced, so that the transistor can have high reliability.

Measurements of parameters of MOS transistors, also known as MOSFETs, such as threshold potentials, require accurate estimates of source and drain series resistance. In cases where connections to the MOSFET include significant external series resistance, as occurs in probing transistors that are partially fabricated or deprocessed, accurate estimates of external resistances are also required. This invention comprises a method for estimating series resistances of MOSFETs, including resistances associated with connections to the MOSFET, such as probe contacts. This method is applicable to any MOSFET which can be accessed on source, drain, gate and substrate terminals, and does not require other test structures or special connections, such as Kelvin connections.

After formation of a gate stack, regions in which a source and a drain are to be formed are recessed through the top semiconductor layer and into an upper portion of a buried single crystalline rare earth oxide layer of a semiconductor-on-insulator (SOI) substrate so that a source trench and drain trench are formed. An embedded single crystalline semiconductor portion epitaxially aligned to the buried single crystalline rare earth oxide layer is formed in each of the source trench and the drain trench to form a recessed source and a recessed drain, respectively. Protrusion of the recessed source and recessed drain above the bottom surface of a gate dielectric can be minimized to reduce parasitic capacitive coupling with a gate electrode, while providing low source resistance and drain resistance through the increased thickness of the recessed source and recessed drain relative to the thickness of the top semiconductor layer.

A segmented capacitive liquid level sensor and a liquid level measuring method thereof, comprising a microprocessor, a sine wave generating circuit connected with the microprocessor, and a multiplex switch connected with the microprocessor and the sine wave generating circuit, A segmented capacitor connected to the multi-way switch, the segmented capacitor is composed of at least two mutually insulated capacitor arrangements, the multi-way switch is connected to each segment of the capacitor in the segmented capacitor respectively, and the microprocessor A leakage resistance detection circuit and a phase difference detection circuit are respectively connected between the multi-way switch and the multi-way switch; the microprocessor controls the multi-way switch to connect the input terminals of each segment capacitor in the segmented capacitor to the sine wave through a charging resistor The generating circuit is connected to the leakage resistance detection circuit and the phase difference detection circuit respectively at the output end. The invention adopts a leakage resistance detection circuit and a phase difference detection circuit to accurately measure the capacitance of each segment of the segmented capacitor, so that the liquid level measurement is more accurate, the reliability is high, and the anti-interference ability is strong.

The invention discloses a test structure, a manufacturing method of the test structure and a test method. The test structure comprises a gate structure, at least two groups of contact hole structure units and at least two layers of metal layers, wherein the at least two groups of contact hole structure units are arranged on an active area of one side of the gate structure; each group of contact hole structure units comprises at least one contact hole structure; the at least two layers of metal layers are arranged on a surface of each group of the contact hole structure units and are arranged with the contact hole structure units in a one-to-one correspondence mode. In the test structure, the metal layers on any two groups of contact hole structure units are taken as probe contact points during a resistance test so as to obtain a source-drain resistance in the test structure so that a structure difference between the test structure and a real device, which is generated because the gate structure is not formed in the test structure, is reduced; and further a difference between the source-drain resistance in the test structure and a source-drain resistance in the real device is reduced and measured value accuracy of the source-drain resistance in the test structure is increased.

The invention provides a self-aligned double-layer channel metallic oxide thin film transistor and a manufacturing method of the self-aligned double-layer channel metallic oxide thin film transistor. The manufacturing method comprises the following steps that a thick high-resistivity metallic oxide semiconductor layer and a thin low-resistivity metallic oxide layer deposit on a substrate, so that double layers of channels are formed; photoetching and etching are carried out on the double layers of channels, so that an active area graph is formed; a gate medium layer and a gate electrode are formed on the double layers of channels; a covering layer with H deposits on the whole substrate, then heat processing is carried out so that H can diffuse to metallic oxide outside the channel area not covered by the gate electrode and the gate medium, and a heavily doped low-resistivity source drain area is formed; a contact hole and a contact electrode are prepared. The self-aligned double-layer channel metallic oxide thin film transistor and the manufacturing method of the self-aligned double-layer channel metallic oxide thin film transistor adopt self-aligned double-layer channel top gate structure, can lower source drain resistance, lower the influence of ambient light on elements, lower off-state current, and improve on-state current and migration rate of the elements.

According to one embodiment, a variable gain control transformer comprises a primary winding connected to differential inputs of the variable gain control transformer, a secondary winding for providing a single ended output to a load, and an output control circuit coupled to the secondary winding, the output control circuit configured to provide up to approximately 12 dB of gain control. Variable gain control may be achieved using first and second variable resistors of the output control circuit, wherein the first and second variable resistors are implemented by respective first and second pluralities of source-drain resistances produced by respective corresponding first and second pluralities of selectable field-effect transistors (FETs). In one embodiment, the variable gain control transformer further comprises a variable capacitance tuning circuit coupled between the differential inputs, the variable capacitance tuning circuit implemented using a plurality of selectable fixed capacitance unit cells.

In HEMTs based on III-nitrides epitaxial films or GaAs, AlGaAs and InGaAs epitaxial films, unwanted microcracks are often formed in the composite epitaxial layers in the channel region during fabrication and operation. These microcracks are caused by strain or stresses due to lattice mismatch and thermal expansion coefficient differences between materials and substrate's. Those microcracks will bring about an increase in source to drain resistance and lead to performance and reliability degradation of the HEMTs and the MMICs containing them. The present invention provides HEMTs with minimized effects of the unwanted microcracks by aligning the channel region long axis to a certain direction so that the channel region long axis forms a right angle with axis of at least one type of the microcracks.