ICP Etching of Tantalum Nitride using Cl2, BCl3 and CF4
Abstract
Tantalum nitride (TaN) is becoming an increasingly common material in semiconductor fabrication, finding a variety of uses such as: metal gates in CMOS technology, electrode materials for capacitors and precision thin film resistors. In patterning TaN films, redeposition of non-volatile etch by-products at the edge of a pattern generates undesirable topography (etch veils) that requires a separate plasma or wet chemical step for removal (deveil). Because deveil processes can have a negative impact on underlying films, it is important to select an etch process whereby sidewall deposits are minimized. We present a study of veil formation during patterned etch of TaN, where the etch terminates on different dielectrics and where different hardmask materials are used. In addition, we present TaN etch rate and selectivity to various materials as a function of processing conditions using Cl2, CF4, and BCl3 gases in an ICP reactor.
- Publication:
-
APS Annual Gaseous Electronics Meeting Abstracts
- Pub Date:
- October 2002
- Bibcode:
- 2002APS..GECHT1005L