Integration, BEOL, and Thermal Stress Impact on CMOS-Compatible Titanium-Based Contacts for III–V Devices on a 300-mm Platform

Titanium-based contacts are envisioned for the integration of III–V device contacts on a 300-mm platform, such as photodetectors, semiconductor optical amplifiers (SOAs), and III–V silicon hybrid lasers. For the first time, the impact of the thermal budgets of process integration, back-end of line (BEOL), and long-term thermal stress on the electrical characteristics of the Ti/p-In0.53Ga0.47As and Ti/n-InP contacts has been investigated. Additional physical characterizations have been used to supplement the electrical properties on both systems. Results have indicated that, given a thermal budget between 350 °C and 450 °C during 60 s right after metal deposition, 1) Ti as a contact metal has led to contact resistivity in low $10^{-{5}}\,\,\Omega \cdot \text {cm}^{{2}}$ for p-contacts and in mid $10^{-{5}}\,\,\Omega \cdot \text {cm}^{{2}}$ for n-contacts, which is in accordance with the device requirements; and 2) process integration, BEOL, and long-term thermal stress will not induce any change of the electrical properties. In the scope of III–V silicon hybrid laser contact integration, Ti has hence been evidenced as a suitable candidate for both p- and n-contacts.