IntroductionThe trend toward smaller MOSFET devices with thinner gate oxide and greater doping is resulting in the increased importance of quantum mechanical effects, which are observed as shifts in threshold voltage and gate capacitance. Predicting these quantum effects requires solving the Schrodinger equation. This article presents the Poisson-Schrodinger solver and recent enhancements implemented in ATLAS from Silvaco.

AbstractImprovement in temperature characteristics of GaN LEDs is important for realizing reliable devices operating at high temperatures. In this article, the thermal characteristics of GaN LEDs have been analyzed by using the ATLAS three dimensional thermal conduction model and thermal heat model. Maximum operation temperature has also been calculated. It was shown that the distribution of lattice temperature using the conventional structure.

Polarization-induced charges at the AlGaN/GaN interface of heterojunction field-effect transistors (HFETs) create a high density, two-dimensional electron gas (2DEG) in the channel. One approach to simulating the 2DEG is to place a fixed positive charge at the AlGaN/GaN interface, thus attracting a fixed quantity of electrons to the channel. Silvaco’s ATLAS software can do this with either an INTERFACE statement or automatically with the use of the POLARIZATION parameter on the REGION statement. This is fine, as far as it goes, but this simple approach glosses over some nuances having to do with the source of carriers in the channel. A paper by Ibbetson, et al.,[1] explored this question theoretically and experimentally.