Ultra-low Contact Resistivity of PtHf Silicide Utilizing Dopant Segregation Process
Abstract
We investigated the dopant segregation (DS) process for PtHf silicide to realize low contact resistivity. After the patterning of SiO2 hard mask and heavily doped n+ diffusion region formation on p-Si(100) substrates, 20 nm-thick PtHf-alloy thin film with 10 nm-thick HfN encapsulating layer was deposited in situ utilizing a PtHf-alloy target by RF magnetron sputtering at room temperature. Then, PH3 ion implantation was carried out for DS followed by silicidation at 450-500°C/5-60 min in N2/4.9%H2 ambient. After Al electrode formation, a sintering process was carried out at 400°C/20 min in N2/4.9%H2 ambient. Ultra-low contact resistivity was achieved for fabricated PtHSi with a DS process on the order of 2.5 × 10-8 Ω cm2 evaluated by the cross-bridge Kelvin resistor method.
- Publication:
-
Journal of Electronic Materials
- Pub Date:
- December 2016
- DOI:
- 10.1007/s11664-016-5002-7
- Bibcode:
- 2016JEMat..45.6323O
- Keywords:
-
- PtHfSi;
- PtHf-alloy target;
- dopant segregation;
- contact resistivity;
- CBKR;
- Schottky barrier height;
- radio frequency magnetron sputtering