The development of low-resistance Ohmic contacts are critical for efficient operation of \(\beta \) -Ga \(_2\) O \(_3\) power and optoelectronic devices. This work investigates the use of an aluminum-doped zinc oxide (AZO) interlayer between \(\beta \) -Ga \(_2\) O \(_3\) and Ti contacts using TCAD Silvaco. The incorporation of a 20 nm AZO layer resulted in linear I-V characteristics. Transmission line method (TLM) analysis showed that the Ti/AZO/ \(\beta \) -Ga \(_2\) O \(_3\) contact achieved a specific contact resistivity of \(4.18 \times 10^{-8}\ \Omega \cdot \text {cm}^2\) and a contact resistance of 44.1 \(\Omega \) at elevated temperatures( \(500^\circ \textrm{C}\) ). These values represent a notable reduction compared to previously reported Ti/ \(\beta \) -Ga \(_2\) O \(_3\) Ohmic contacts, demonstrating the effectiveness of the AZO interlayer. Furthermore, the optimized contacts are implemented in an AlN/ \(\beta \) -Ga \(_2\) O \(_3\) HEMT, demonstrating enhanced drain current and transconductance due to polarization-induced 2DEG formation. These results highlight the effectiveness of AZO in contact engineering and its potential for high-power switching and high-frequency applications.
