Transistor

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

Contact effects in polymer transistors

Abstract: Polymer thin film transistors based on the polyfluorene F8T2 exhibit a nonohmic contact resistance, particularly when in the coplanar device geometry. We show how to obtain the current–voltage relation for the contact from the transistor output characteristics measured with different channel lengths. The diode-type relation is attributed to the contact injection properties of the metal Schottky barrier. No significant increase in mobility with gate or drain field is observed.

MINIMOS—A two-dimensional MOS transistor analyzer

Abstract: We describe a user-oriented software tool-MINIMOS-for the two-dimensional numerical simulation of planar MOS transistors. The fundamental semiconductor equations are solved with sophisticated programming techniques to allow very low computer costs. The program is able to calculate the doping profiles from the technological parameters specified by the user. A new mobility model has been implemented which takes into account the dependence on the impurity concentration, electric field, temperature, and especially the distance to the Si-SiO 2 interface. The power of the program is shown by calculating the two-dimensional internal behavior of three MOST's with 1-µm gate length differing in respect to the ion-implantation steps. In this way, the threshold voltage shift by a shallow implantation and the suppression of punchthrough by a deep implantation are demonstrated. By calculating the output characteristics without and with mobility reduction, the essential influence of this effect is shown. From the subthreshold characteristics, the suppression of short-channel effects by ion implantation becomes apparent. The MINIMOS program is available for everyone for just the handling costs.

Evaluation of a dual bias dual metal oxide-silicon semiconductor field effect transistor detector as radiation dosimeter

Abstract: A new type of direct reading semiconductordosimeter has been investigated as a radiation detector for photon and electron therapy beams of various energies. The operation of this device is based on the measurement of the threshold voltage shift in a custom‐built metal oxide‐silicon semiconductorfield effect transistor(MOSFET). This voltage is a linear function of absorbed dose. The extent of the linearity region is dependent on the voltage controlled operation during irradiation. Operating two MOSFETS at two different biases simultaneously during irradiation will result in sensitivity (V/Gy) reproducibility better than ±3% over a range in dose of 100 Gy and at a dose per fraction greater than 20×10−2 Gy. The modes of operation give this device many advantages, such as continuous monitoring during irradiation, immediate reading, and permanent storage of total dose after irradiation. The availability and ease of use of these MOSFETdetectors make them very promising in clinical dosimetry.

Characteristics of the metal-Oxide-semiconductor transistors

Abstract: The theory of the MOS transistor in the gradual channel approximation is presented with the assumption of constant surface and bulk charge, and constant surface mobility. From the simple theory, the complete design equations are derived and design curves are calculated. From the analysis, the equivalent circuit parameters of the device are related to the basic properties of the material and geometry of the device. The simple theory is then critically compared with experimental measurements of MOS transistors with circular geometry. The comparison shows good general agreement with the theory of the dc characteristics but discrepancies are found for the differential characteristics such as the transconductance and the gate capacitance. The possible sources of the discrepancies are discussed.

Volatile and non-volatile memories in silicon with nano-crystal storage

Abstract: A single transistor memory structure, with changes in threshold voltage exceeding /spl ap/0.25 V corresponding to single electron storage in individual nano-crystals, operating in the sub-3 V range, and exhibiting long term to non-volatile charge storage is reported. As a consequence of Coulombic effects, operation at 77 K shows a saturation in threshold voltage in a range of gate voltages with steps in the threshold voltage corresponding to single and multiple electron storage. The plateauing of threshold shift, operation at ultra-low power, low voltages, and single element implementation utilizing current sensing makes this an alternative memory at speeds lower than those of DRAMs and higher than those of E/sup 2/PROMs, but with potential for significantly higher density, lower power, and faster read.