Abstract: A junction field effect transistor includes a channel region, a gate region coupled to the channel region, a well tap region coupled to the gate region and the channel region, and a well region coupled to the well tap region and the channel region. A double gate operation is achieved by this structure as a voltage applied to the gate region is also applied to the well region through the well tap region in order to open the channel from both the gate region and the well region.

Abstract: A system for identifying asserted signals includes a plurality of input ports, a priority encoding module, and a match module. The plurality of input ports receive one of a plurality of input signals. The priority encoding module is coupled to the plurality of input ports and outputs a signal indicating a highest-priority input signal that is asserted. The match module is also coupled to the plurality of input ports and receives a plurality of match detect signals from the priority encoding module. Each match detect signal is associated with a particular input signal and indicates whether another input signal having a higher-priority than the associated input signal is asserted. The match module also generates a multiple match signal based on the input signals and the match detect signals. The multiple match signal indicates whether more than one of the input signals is asserted.

Abstract: A junction field effect transistor comprises a semiconductor substrate and a well region formed in the substrate. A source region of a first conductivity type is formed in the well region. A drain region of the first conductivity type is formed in the well region and spaced apart from the source region. A channel region of the first conductivity type is located between the source region and the drain region and formed in the well region. A gate region of a second conductivity type is formed in the well region. The transistor further includes first, second, and third connection regions. The first connection region is in ohmic contact with the source region and formed of silicide. The second connection region is in ohmic contact with the drain region and formed of silicide. The third connection region in ohmic contact with the gate region.

Abstract: A method for fabricating a semiconductor device comprises depositing a first layer of oxide on at least a portion of a channel of a transistor. The method further comprises depositing a layer of nitride on the first layer of oxide and etching at least a portion of the layer of nitride to the first layer of oxide. The method further comprises depositing a second layer of oxide and planarizing the oxide to expose at least a portion of the layer of nitride. The method further comprises stripping at least a portion of the layer of nitride to create one or more notches and removing at least a portion of the first layer of oxide. The method further comprises depositing a layer of polysilicon, wherein at least a portion of the layer of polysilicon is deposited into at least one of the one or more notches.

Abstract: A process for manufacturing a Junction Field-Effect Transistor, comprises doping a semiconductor material formed on an insulating substrate with impurities of a first conductivity type to form a well region. The process continues by implanting impurities of a second conductivity type into said well region to form a channel region, and by implanting impurities of the first conductivity type in said well region to form a back gate region. The process continues by forming a trench to expose at least one sidewall of said channel region, wherein the trench extends far enough along the sidewall to expose at least a portion of said back gate region. The process continues by depositing polysilicon to fill said trench along the at least one sidewall of said channel region and at least a portion of said back gate region, wherein at least a portion of the polysilicon will form a gate contact. The polysilicon is then doped with impurities of a first conductivity type.

Abstract: A transistor includes a channel region with a first portion and a second portion. A length of the first portion is smaller than a length of the second portion. The first portion has a higher threshold voltage than the second portion. The lower threshold voltage of the second portion allows for an increased ON current. Despite the increase attained in the ON current, the higher threshold voltage of the first portion maintains or lowers a relatively low OFF current for the transistor.

Abstract: A level shifting circuit can include a first driver junction field effect transistor (JFET) having a source coupled to a reference supply node and a second driver JFET of a second conductivity type having a source coupled to a boosted supply node, and a first charge pump circuit. The first charge pump circuit can be coupled between the first driver control node and an input node coupled to receive an input signal, and can couple a first terminal of a first capacitor between a reference supply node and a power supply node in response to an input signal. The power supply node can be coupled to receive a power supply potential, the reference supply node can be coupled to receive a reference potential, and the boosted power supply node can be coupled to receive a boosted potential. The reference potential can be between the power supply potential and the boosted potential.

Abstract: A scalable device structure and process for forming a normally off JFET with 45 NM linewidths or less. The contacts to the source, drain and gate areas are formed by forming a layer of oxide of a thickness of less than 1000 angstroms, and, preferably 500 angstroms or less on top of the substrate. A nitride layer is formed on top of the oxide layer and holes are etched for the source, drain and gate contacts. A layer of polysilicon is then deposited so as to fill the holes and the polysilicon is polished back to planarize it flush with the nitride layer. The polysilicon contacts are then implanted with the types of impurities necessary for the channel type of the desired transistor and the impurities are driven into the semiconductor substrate below to form source, drain and gate regions.

Abstract: This invention describes a method of building complementary logic circuits using junction field effect transistors in silicon. This invention is ideally suited for deep submicron dimensions, preferably below 65 nm. The basis of this invention is a complementary Junction Field Effect Transistor which is operated in the enhancement mode. The speed-power performance of the JFETs becomes comparable with the CMOS devices at sub-70 nanometer dimensions. However, the maximum power supply voltage for the JFETs is still limited to below the built-in potential (a diode drop). To satisfy certain applications which require interface to an external circuit driven to higher voltage levels, this invention includes the structures and methods to build CMOS devices on the same substrate as the JFET devices.

Abstract: A JFET structure with self-aligned metal source, drain and gate contacts with very low resistivity and very small feature sizes. Small source, drain and gate openings are etched in a thin dielectric layer which has a thickness set according to the desired source, gate and drain opening sizes, said dielectric layer having a nitride top layer. Metal is deposited on top of said dielectric layer to fill said openings and the metal is polished back to the top of the dielectric layer to achieve thin source, drain and gate contacts. Some embodiments include an anti-leakage poly-silicon layer lining the contact holes and all embodiments where spiking may occur include a barrier metal layer.

Abstract: A semiconductor memory device including a dynamic random access memory (DRAM) cell and a ternary content addressable memory (TCAM) cell is disclosed. The DRAM cell may include a data storing portion and a data read portion. The data storing portion and data read portion comprising p-channel junction field effect transistors. The TCAM cell including an x-cell, y-cell, and comparator circuit. The x-cell, y-cell, and comparator circuits comprising p-channel JFETs.

Abstract: A switching circuit can have a plurality of first signal lines of a programmable logic device, a plurality of second signal lines of the programmable logic device, and a plurality of switch elements. Each switch element can selectively couple one first signal line to a second signal line and include one or more switch junction field effect transistors (JFETs) having a first control gate separated from a second control gate by a channel region.

Abstract: Circuits using four terminal junction field effect transistors (JFETs) are disclosed. Such circuits can include various static and dynamic logic circuits, flip-flops, multiplexer, tri-state driver, phase detector, logic having variable speeds of operation, and/or analog circuit with such four terminal JFETs operating in a linear or nonlinear mode.

Abstract: A method for modeling a circuit includes generating a circuit model based on a netlist that defines a plurality of connections between a plurality of circuit elements. The circuit model includes a model of one or more of the circuit elements. The method further includes determining a wire width associated with at least a selected connection based, at least in part, on design rules associated with the netlist. Additionally, the method includes determining a wire thickness associated with the selected connection based, at least in part, on a signal delay associated with the wire thickness. Furthermore, the method also includes routing the selected connection in the circuit model using a wire having a width substantially equal to the wire width calculated for the connection and a thickness equal to the wire thickness calculated for the connection and storing the circuit model in an electronic storage media.

Abstract: A semiconductor device includes a semiconductor substrate that includes a substrate layer having a first composition of semiconductor material. A source region, drain region, and a channel region are formed in the substrate, with the drain region spaced apart from the source region and the gate region abutting the channel region. The channel region includes a channel layer having a second composition of semiconductor material. Additionally, the substrate layer abuts the channel layer and applies a stress to the channel region along a boundary between the substrate layer and the channel layer.

Abstract: Circuits using four terminal junction field effect transistors (JFETs) are disclosed. Such circuits can include various static and dynamic logic circuits, flip-flops, multiplexer, tri-state driver, phase detector, logic having variable speeds of operation, and/or analog circuit with such four terminal JFETs operating in a linear or nonlinear mode.

Abstract: This invention describes a method of building complementary logic circuits using junction field effect transistors in silicon. This invention is ideally suited for deep submicron dimensions, preferably below 65 nm. The basis of this invention is a complementary Junction Field Effect Transistor which is operated in the enhancement mode. The speed-power performance of the JFETs becomes comparable with the CMOS devices at sub-70 nanometer dimensions. However, the maximum power supply voltage for the JFETs is still limited to below the built-in potential (a diode drop). To satisfy certain applications which require interface to an external circuit driven to higher voltage levels, this invention includes the structures and methods to build CMOS devices on the same substrate as the JFET devices.

Abstract: A method for using an inverter with a pair of complementary junction field effect transistors (CJFET) with a small linewidth is provided. The method includes having an input capacitance for said CJFET inverter to be less than the corresponding input capacitance of a CMOS inverter of similar linewidth. The CJFET operates at a power supply with a lesser value than the voltage drop across a forward-biased diode having a reduced switching power as compared to said CMOS inverter and having a propagation delay for said CJFET inverter that is at least comparable to the corresponding delay of said CMOS inverter.

Abstract: A JFET integrated onto a substrate having a semiconductor layer at least and having source and drain contacts over an active area and made of first polysilicon (or other conductors such as refractive metal or silicide) and a self-aligned gate contact made of second polysilicon which has been polished back to be flush with a top surface of a dielectric layer covering the tops of the source and drain contacts. The dielectric layer preferably has a nitride cap to act as a polish stop. In some embodiments, nitride covers the entire dielectric layer covering the source and drain contacts as well as the field oxide region defining an active area for said JFET. An embodiment with an epitaxially grown channel region formed on the surface of the substrate is also disclosed.

Abstract: A Junction Field-Effect transistor with no surface contact for the back gate and twice as much transconductance in the channel and with a higher switching speed is achieved by intentionally shorting the channel-well PN junction with the gate region. This is achieved by intentionally etching away field oxide outside the active area at least in the gate region so as to expose the sidewalls of the active area down to the channel-well PN junction or a buried gate which is in electrical contact with the well. Polysilicon is then deposited in the trench and doped heavily and an anneal step is used to drive impurities into the top and sidewalls of the channel region thereby creating a “wrap-around” gate region which reaches down the sidewalls of the channel region to the channel-well PN junction.