Ultrathin Body GaN-on-Insulator Quantum Well FETs With Regrown Ohmic Contacts

Guowang Li, Ronghua Wang, Jia Guo, Jai Verma, Zongyang Hu, Yuanzheng Yue, Faiza Faria, Yu Cao, Michelle Kelly, Thomas Kosel, Huili Xing, Debdeep Jena
2012 IEEE Electron Device Letters  
A technology similar to silicon-on-insulator is highly desirable for III-V electronics to support scaling for future generations. This letter reports the first realization of strained GaN quantum-well transistors embedded in unstrained AlN as the insulator. The molecular beam epitaxy (MBE)-grown heterostructure consisting of an ultrathin GaN channel buried in strain-free AlN barriers is favorable for scaling by the suppression of shortchannel effects. Ohmic contacts are realized with
more » ... heavily Si-doped n + GaN. For long-channel devices, a saturation drain current of ∼0.7 A/mm at V GS = +3 V and a peak extrinsic transconductance of ∼160 mS/mm around V GS = +1 V are measured at V DS = +10 V. No hysteresis is observed in the C-V measurement, indicating the high quality of all binary nitride heterostructures. The demonstrated device structure offers a high promise for high-frequency and high-power applications in the future. The strain-free barrier has the potential to enhance the reliability of GaN transistors. Index Terms-Aluminum nitride (AlN), gallium nitride, molecular beam epitaxy (MBE), quantum well (QW), transistor, ultrathin body (UTB).
doi:10.1109/led.2012.2186628 fatcat:mh3t45phxjekjlmkauljbmixia