Transistor

About: Transistor is a research topic. Over the lifetime, 138090 publications have been published within this topic receiving 1455233 citations.

Comparing carbon nanotube transistors - the ideal choice: a novel tunneling device design

Abstract: Three different carbon nanotube (CN) field-effect transistor (CNFET) designs are compared by simulation and experiment. While a C-CNFET with a doping profile similar to a "conventional" (referred to as C-CNFET in the following) p-or n-MOSFET in principle exhibits superior device characteristics when compared with a Schottky barrier CNFET, we find that aggressively scaled C-CNFET devices suffer from "charge pile-up" in the channel. This effect which is also known to occur in floating body silicon transistors deteriorates the C-CNFET off-state substantially and ultimately limits the achievable on/off-current ratio. In order to overcome this obstacle we explore the possibility of using CNs as gate-controlled tunneling devices (T-CNFETs). The T-CNFET benefits from a steep inverse subthreshold slope and a well controlled off-state while at the same time delivering high performance on-state characteristics. According to our simulation, the T-CNFET is the ideal transistor design for an ultrathin body three-terminal device like the CNFET.

Low-voltage, 30 nm channel length, organic transistors with a self-assembled monolayer as gate insulating films

Abstract: We made nanometer-scale (gate length of 30 nm) organic thin-film transistors using a self-assembled monolayer (2 nm thick) as a gate insulator. The fabrication steps combine electron-beam lithography and lift-off techniques for the deposition of both metal electrodes and organic semiconductors with a chemical approach (self-assembly of organic molecules) to fabricate the gate insulator. Good performances of these transistors (with a record subthreshold slop of 350 mV/decade and a cutoff frequency of 20 kHz) and low-voltage operation (<2 V) are demonstrated down to a gate length of 200 nm. A gate voltage modulation of the source-to-drain tunnel current is demonstrated for the 30 nm gate length device.

Silicon-germanium base heterojunction bipolar transistors by molecular beam epitaxy

Abstract: The devices were fabricated using molecular-beam epitaxy (MBE), low-temperature processing, and germanium concentrations of 0, 6%, and 12%. The transistors demonstrate current gain, and show the expected increase in collector current as a result of reduced bandgap due to Ge incorporation in the base. For a 1000-AA base device containing 12% Ge, a six-times increase in collector current was measured at room temperature, while a 1000-times increase was observed to 90 K. The temperature dependence of the collector current of the Si/sub 0.88/Ge/sub 0.12/ base transistor is consistent with a bandgap shrinkage in the base of 50 meV. For the homojunction transistors, base widths as thin as 800 AA were grown, corresponding to a neutral base width of no more than 400 AA. >

The Design of High-Performance Analog Circuits on Digital CMOS Chips

Abstract: Devices available in digital oriented CMOS processes are reviewed, with emphasis on the various modes of operation of a standard transistor and their respective merits, and on additional specifications required to apply devices in analog circuits. Some basic compatible analog circuit techniques and their related tradeoffs are then surveyed by means of typical examples. The noisy environment due to cohabitation on the chip with digital circuits is briefly evoked.