| A. STACH |
| Institute for Microelectronics |
| A-1040, Gusshausstrasse 27-29 |
| Vienna, Austria |
| R. SABELKA |
| Institute for Microelectronics |
| A-1040, Gusshausstrasse 27-29 |
| Vienna, Austria |
| S. SELBERHERR |
| Institute for Microelectronics |
| A-1040, Gusshausstrasse 27-29 |
| Vienna, Austria |