Hints, Tips and Solutions&November 2005

Q. How can I create a non planar structure using III-V materials for Device Analysis when the materials I want to use are not in the ATHENA data base.

A. There are many materials in the ATLAS device simulator data base that are not in the ATHENA database, primarily because most of these exotic materials are usually deposited epitaxially and very little actual processing takes place in terms of implantation, diffusion and heat treatments.

However, it is often desired to create a device with non vertical side-walls or a device where a non planar realistic deposit of an inter-layer di-electric plays a key role in the device operation. In these circumstances it is necessary to use the ATHENA process simulator. However, if the process simulator does not contain the exotic materials of interest in it’s process data base, a user defined material must be used.

There is a special feature in the Silvaco process simulator, ATHENA , which converts unknown user defined materials into known device simulator materials so long as the user defined material is given the exact same name as the known device simulator material.

All that is required now to complete device construction in the process simulator, ATHENA , is to define the dopant materials as either donor or acceptor using the impurity statement.

An example of the first few lines of an ATHENA deck is given below. The example demonstrates how to define the user defined material as both the starting substrate material and as a deposited layer