KTH Advances TCAD Program in Sweeden

Prof. Mikael Ostling
Summary of Si technology research performed at the
Department of Electronics, Royal Institute of Technology,
Stockholm, Sweden

The centre for microelectronics (Electrum) in Kista-Stockholm was established in 1988 and currently has a strong program in Si technology and optoelectronics. We have a good laboratory capability with a clean room (class10-100) and area of 1300 sq. meters. In Si technology we have since long focused on issues related to sub-micron processes and devices. Currently a demonstrator project for fast bipolar devices is run in a consortium consisting of several university departments and with Ericsson Components as a major industrial partner. Previous research in this area had led to a technology transfer of a 15 GHz bipolar process (now in operation at Ericsson). The goals with the present research are bipolar devices with ft of 60 GHz and circuit clock rates of 10-20 GHz.

The department of electronics is vertically integrated from basic materials research up to a systems design level. This setting gives us the possibility to develop silicon IC-demonstrators.

Much effort is concentrated on process design for good control of shallow doping profiles and limited temperature processing based on rapid thermal processing and in-situ doping.

Device and circuit optimization are also addressed. A complete set of new test structures for both high frequency characterization as well as process monitors has been developed. We have recently adopted the Virtual Wafer Fab package from Silvaco for the TCAD part of the project. Initially, most efforts have been spent on 2-D process and device simulation. The feedback from the involved PhD students has been positive and the package has turned out to be user-friendly. We have currently 10 licenses which makes it possible to use the package in teaching and recently we finished a course in advanced semiconductor devices with a project work based on device simulation in Atlas. Both graduate students and engineers from industry attended the course and all were quite satisfied with the programs and the user interface.