Sah C-T – TechConnect Briefs

Theory of Bipolar MOSFET (BiFET) with Electrically Short Channels

Jie B.B., Sah C-T, Univesity of Florida, US

Bipolar MOSFETs with a pure base and two MOS gates usually have electrically short channels compared with its intrinsic Debye length of about 25μm at room temperatures. This short channel effect was missed by all [...]

Interface-trap Charges on Recombination DC Current-Voltage Characteristics in MOS transistors

Chen Z., Jie B.B., Sah C-T, Nanyang Technological University, SG

The interface traps and trapped charges along the surface channel region are generated during transistor stress or operation and primarily responsible for the changes of device properties. The threshold voltage is varied by the generation [...]

The Bipolar Field-Effect Transistor Theory (B. Latest Advances)

Sah C-T, Jie B.B., University of Florida, US

Latest advances are presented on theoretical device and circuit characterizations of the Bipolar Field effect transistor (BiFET) [1]. The 2 Dimensional (2 D) rectangular geometry of the transistor (uniform in the width direction) is employed [...]

The Bipolar Field-Effect Transistor Theory (A. Summary of Recent Progresses)

Jie B.B., Sah C-T, Peking University, CN

Field effect transistor (FET) was conceived 80 years ago in Lilienfeld ‘s 1926 1932 patents [1]. Shockley 1952 [2] invented the volume channel FET 55 years ago using two opposing p/n junctions as gates on [...]

The Driftless Electromigration Theory (Diffusion-Generation-Recombination-Trapping)

Sah C-T, Jie B.B., University of Florida, US

Electromigration (EM) is the transport of atoms and ions in metals at high electrical current density (>100kA/cm^2) leaving behind voids. It was delineated in 1961 by Huntington [1] in gold wire, and empirically modeled by [...]

Analytical Solutions for Long-Wide-Channel Thick-Base MOS Transistors I. Effects of Remote Boundary Conditions and Body Contacts

Jie B.B., Sah C-T, Peking University, CN

Analytical solutions and computed characteristics for long-wide-channel thick-base MOS transistors are reported. The second generation industrial-consensus surface potential approach is used. Decomposition of the 2-Dimensional transistor problem into two 1-D problems follows the 1966-Pao-Sah current- [...]

High Conentration of Interface Traps in MOS Transistor Modeling

Chen Z., Jie B.B., Sah C-T, Xiamen University, CN

Modifications of the MOS capacitor and transistor characteristics by the presence of a high concentration of interface traps are described. Change or distortion of the gate/base voltage dependent characteristics are presented, such as the gate [...]

A History of Electronic Traps on Silicon Surfaces and Interfaces

Sah C-T, Jie B.B., Chen Z., University of Florida, US

A review of the electronic or electron and hole traps on silicon surfaces and interfaces is given. They are increasingly affecting the electrical signal properties of silicon diodes and transistors as the technologies for digital, [...]

Accuracy of Surface-Potential-Based Long-Wide-Channel MOS Transistor Compact Models

Jie B.B., Sah C-T, University of Florida, US

Frequently asked questions are addressed, “How accurate are the approximate long-and-wide-channel MOS transistors baseline models that have been used to develop the compact models for computer-aided circuit designs?” Three commonly used surface-potential (US=q*PSIS/kT) approximations of [...]

A History of MOS Transistor Compact Modeling

Sah C-T, University of Florida, US

The MOSFET (Metal-Oxide-Silicon Field-Effect- Transistor) or MOS Transistor (MOST) is a three dimensional electronic device. It operates on the conductivity modulation principle in a thin semiconductor layer by a controlling electric field to give amplifying [...]