• Simulation Standard Technical Journal

Simulation Standard Technical Journal

A Journal for Process and Device Engineers

TCAD Simulation of Electric Field Distribution in Gallium Nitride Trench-based Power Devices

IntroductionGallium nitride (GaN)-based devices are excellent candidates for high-voltage and high-power applications, due to the superior physical properties of GaN compared to Si, SiC, and GaAs. Recently, GaN vertical devices have attracted increased attention, due to their advantages over GaN lateral devices, including high breakdown voltage (BV) and current capability for a given chip size, and superior thermal performance.1 Recent demonstrations of high-performance vertical GaN diodes2–4 and transistors5–9 have made vertical structures very promising for GaN power devices.

Channel-length Dependence of a-IGZO TFTs with Self-heating Effects

IntroductionAmorphous In-Ga-Zn-O thin-film transistors (a-IGZO TFTs) show a high mobility, a small sub-threshold swing, and a low OFF-current, and they are considered to be one of the most promising TFT for new flat-panel displays (FPDs). The high mobility originates from the unique electron transport in a-IGZO. The transport properties are different from those in conventional semiconductor materials like Si, for example, the mobility increases with increase of the electron concentration and/or temperature. Therefore, the new mobility model for a-IGZO is necessary. In addition, as pixel sizes in the FPDs decreases, a channel-length, L, of a-IGZO TFTs becomes shorter. It indicates that it is important to understand the operation of short-channel a-IGZO TFTs.

Simulation of Different Tunnel Junctions in InGaP/GaAs, InGaP/CdTe Dual Junction Solar Cells

Abstract — Dual junction solar cells were simulated using Silvaco TCAD tool with various tunnel junction material compositions. InGaP/GaAs dual junction solar cells were simulated with 10 different tunnel junction combinations. The highest efficiencies were from InGaP/AlGaAs and InGaP/InGaP tunnel junctions at 31.82% and 31.75%. InGaP/CdTe solar cells were also simulated with four different tunnel junction combinations. InGaP/InGaP tunnel junction was found to be most efficient with 37.29% which is consistent with experimental data. Three of four InGaP/CdTe dual junction solar cells were simulated to have higher efficiency values than all InGaP/GaAs solar cells.

Hints, Tips and Solutions – July, August, September 2019

Q. Is it possible to emulate a deep reactive ion etch process (e.g. deep trench with scalloped sidewalls) without using a physical based process simulation, such as Victory Process?To study a non-ideal geometry and its impact on device performance, TCAD device engineers may want to generate structures with complex geometries quickly, without the added details of physically-based process simulation.

Process Simulation – New Features in 2019 Baseline Release

2019 baseline release of Victory Process includes improvements and extensions to the following modules:Physical etching/deposition Stress simulation Annealing/oxidation

Meshing – New Features in 2019 Baseline Release

The 2019 TCAD baseline release of Victory Mesh now contains Solid Modeling functionality. The term Solid Modeling is used to refer to a methodology that generates or manipulates a device via geometrical operations, for example, bending, mirroring and joining or insertion.