Drain-induced barrier lowering

About: Drain-induced barrier lowering is a research topic. Over the lifetime, 6163 publications have been published within this topic receiving 101547 citations.

Bulk charge modulated device photocell

Abstract: A bulk charge modulated MOSFET for sensing light comprising a semiconductor substrate with a gate region of a first conductivity type formed in the substrate. The gate region forms a potential well for carriers of the first conductivity type. The well is formed at a substantial depth from the surface of the gate region. The carriers are formed responsive to incident light. The gate region collects the carriers generated at depths less than the well. A source region of a second conductivity type is formed in the semiconductor substrate laterally adjacent the gate region. The source region is operable to sense a change in threshold voltage of the MOSFET responsive to the collection of carriers by the gate region. A drain region of the second conductivity type is formed in the layer adjacent the gate region and spaced from the source. The drain region is connected to a voltage source. The voltage source is pulsed to create a large potential well that extends under the gate region from the source to the drain during charge integration period and a smaller potential well during readout period.

EEPROM cell with the drain diffusion region self-aligned to the tunnel oxide region

Abstract: A method of semiconductor fabrication, in which a single aperture is used to define both a thin oxide tunneling region and a drain diffusion region in a self-aligned fashion, produces a device structure suitable for use in an electrically-erasableread-only memory (EEPROM) cell. A gate oxide is grown, then a photoresist mask is formed having a slit for ion implantation into the drain diffusion region. The oxide within the slit is etched away, and ion implantation forms a drain diffusion region. After the mask is stripped away, a healing furnace cycle removes the implant damage. A thin tunnel oxide layer is grown over the drain diffusion region, and then a polysilicon floating gate is formed so that one edge of this gate intersects a portion of the area of tunnel oxidation so as to form a small region of tunnel oxide under the floating gate. The process sequence then reverts to a conventional MOS flow. The self-aligned drain diffusion region and tunnel oxide region can be used in a variety of EEPROM cell designs. One embodiment involves a double-polysilicon, single-metal process in which three diffusion regions are used to form the EEPROM cell. The second layer of polysilicon overlies the floating gate and forms a control gate word line. The control gate and the floating gate overly the channel between the drain diffusion region and a common source diffusion region. The first layer of polysilicon is also used to form a select gate overlying the channel between the drain diffusion region and a select drain diffusion region. The metal layer provides contact to the select drain diffusion region and forms the bit line.

Charge pump circuit without body effects

Abstract: A charge pump circuit has input and output nodes, a first transistor, a second transistor, a third transistor, a first capacitor, and a second capacitor. A drain of the first transistor and a drain of the second transistor are connected to the input node. A source of the second transistor and a drain of the third transistor are connected to the output node. The first capacitor is connected to a gate of the second transistor. The third transistor is connected to a substrate and a source of the second transistor. When the first transistor is turned on, a voltage at the input node will charge the first capacitor. When the second transistor is turned on, the third transistor is turned on simultaneously so that the substrate and the source of the second transistor will reach the same voltage level. Then, voltage at the input node will charge the second capacitor.

Fermi-threshold field effect transistors including source/drain pocket implants and methods of fabricating same

Abstract: A Fermi-FET, including but not limited to a tub-FET, a contoured-tub Fermi-FET or a short channel Fermi-FET includes a drain extension region of the same conductivity type as the drain region and a drain pocket implant region of opposite conductivity type from the drain region The drain pocket implant region acts as a drain field stop to reduce or prevent drain-to-source field reach-through Reduced low drain field threshold voltage, significantly reduced drain induced barrier lowering and reduced threshold dependence on channel length may be obtained, resulting in higher performance in short channels