On the optimization of VLSI contacts
Abstract
The contact-resistance characteristic of silicon devices has been a subject of research and development since the early days of silicon integrated-circuit technology. The contact-chain losses suffered by very large scale integration (VLSI), however, have made the minimization of contact resistance a critical parameter due to the large number of contacts per circuit and due to the increase of contact resistance with decreasing contact size. This paper will present a brief review of the theory of contact resistance, the literature, measurement techniques, and of the transmission-line model (TLM) for analyzing contact-resistance data. Contact-resistance data pertaining to shallow high-conductivity contacts for VLSI will be presented as a function of the junction parameters (implant dose, etc.) and of the contact area for BF2 and arsenic implants with aluminum-silicon metallization. Contact-resistance data of a sputtered molybdenum silicide contact barrier for boron and arsenic implants versus contact area will also be presented and compared to the aluminum-silicon control samples with a discussion regarding the uniformity of contacts to silicon.
- Publication:
-
IEEE Transactions on Electron Devices
- Pub Date:
- March 1985
- DOI:
- 10.1109/T-ED.1985.21999
- Bibcode:
- 1985ITED...32..682M
- Keywords:
-
- Arsenic;
- Boron Fluorides;
- Contact Resistance;
- Doped Crystals;
- Ion Implantation;
- Silicon;
- Very Large Scale Integration;
- Energy Bands;
- Transmission Lines;
- Volt-Ampere Characteristics;
- Electronics and Electrical Engineering