Performance Improvement of ${\rm HfO}_{2}/{\rm SrTiO}_{3}$ Hetero-Oxide Transistors Using Argon Bombardment

An effective interface engineering method is developed to improve performance of SrTiO
₃
-based hetero-oxide transistors. HfO
₂
/SrTiO
₃
hetero-oxide transistors made on argon ions bombarded SrTiO
₃
surfaces show eight times increase in drive currents and more than five times increase in mobility when compared with the un-bombarded HfO
₂
/SrTiO
₃
transistors. The improvement is attributed to the Fermi-level shift as the results of the bombardment. These HfO
₂
/SrTiO
₃
-based nMOSFETs show field-effect electron mobility up to 4.2 cm
²
/Vs, which is among the best results ever reported.