Advantages
- Suitable for miniaturization of semiconductor devices and power semiconductors.
- Excellent thermal stability, can be used for high-temperature processes or conditions.
- Formed with generally used metals.
Background and Technology
In semiconductor devices such as MOSFETs, silicide films are used to realize low contact resistivity metal/semiconductor junctions at the source/drain (S/D) electrodes on Si substrates. Silicide films are formed by reaction of Si and metal thin film deposited on the Si substrate by annealing. In recent years, in accordance with the miniaturization of devices, S/D junction area has been required to be ultra-thin and low-resistance. NiSi, which consumes less Si and shows good current characteristics, has been widely used. However, in high temperature conditions NiSi has problems such as increased Si consumption, high resistivity, and deteriorated roughness due to the phase transition to NiSi2. So, the development of a silicide film with excellent electrical characteristics is desired.
Associate Professor Shun-ichiro Ohmi of Tokyo Institute of Technology focused on Pt and Pd, which have excellent thermal stability and low Si consumption for silicidation. On the other hand, these silicide films have a high work function, which causes a large potential barrier with the Si substrate and unintentional parasitic resistance. This problem was solved by forming a silicide alloying with a low work function metal such as Hf.
Data
・PtHf alloy films were deposited on p-Si(100) and n-Si(100) substrates by sputtering and after ion implantation for impurity segregation. Silicidation was carried out at 500°C /20 min.
・Achieved 10-9Ωcm2 in CBKR (Cross-Bridge Kelvin Resistor) evaluation.
Patents and Paper
- Patent registered: JP.6455847, US.10246770, KR.102012118, TW. I612146
- IEICE TRANSACTIONS on Electronics Vol. E102-C No. 6 pp. 453-457 (2019)
Principal Inventor
Shun-ichiro Ohmi (Associate Professor, Tokyo Institute of Technology)
Next Step
- Tech Manage is now looking for a company to research and develop semiconductor devices by licensing or collaborate with us on this technology.
- Meeting (including web meeting) with the inventor is available.
Project No. MO-04835