130 mA/mm \(\beta\)-Ga\(_2\)O\(_3\) MESFET with Low-Temperature MOVPE-Regrown Ohmic Contacts

• Published in: arXiv.org
• Main Authors: Bhattacharyya, Arkka, Roy, Saurav, Praneeth Ranga, Shoemaker, Daniel, Song, Yiwen, James Spencer Lundh, Choi, Sukwon, Krishnamoorthy, Sriram
• Format: Paper
• Language: English
• Published: Ithaca Cornell University Library, arXiv.org 26.07.2021
• Subjects: Contact resistance; Epitaxial growth; Field effect transistors; Gallium; Infrared imaging; Low temperature; Metalorganic chemical vapor deposition; Nanoparticles; Semiconductor devices; Silicon; Thermal analysis; Thermal management; Thermography; Vapor phase epitaxy; Vapor phases

We report on the demonstration of metalorganic vapor phase epitaxy-regrown (MOVPE) ohmic contacts in an all MOVPE-grown \(\beta\)-Ga\(_2\)O\(_3\) metal-semiconductor field effect transistor (MESFET). The low-temperature (600\(^{\circ}\)C) heavy (n\(^{+}\)) Si-doped regrown layers exhibit extremely high conductivity with sheet resistance of 73 \(\Omega\)/\(\square\) and record low metal/n\(^{+}\)-Ga\(_2\)O\(_3\) contact resistance of 80 m\(\Omega\).mm and specific contact resistivity of 8.3\(\times\)10\(^{-7}\) \(\Omega\).cm\(^{2}\) were achieved. The fabricated MESFETs exhibit a maximum drain-to-source current of 130 mA/mm, a high I\(_{ON}\)/I\(_{OFF}\) of \(>\)10\(^{10}\) with a high power FOM of 25 MW/cm\(^{2}\) were achieved without any field plates. Nanoparticle-assisted Raman thermometry, thermal modeling, and infrared thermography were performed to assess the device self-heating under the high current and power conditions. This demonstration shows the promise of MOVPE technique for the realization of high-performance lateral \(\beta\)-Ga\(_2\)O\(_3\) devices and also highlights the need for device-level thermal management.