[17p-A307-1~10] Latest trend of device technologies for quantum computing

[17p-A307-2] Uniformity improvements of Josephson-junction characteristics for integration of superconducting qubits

〇Tsuyoshi Takahashi^1,2, Norinao Kouma^1,2, Yoshiyasu Doi^1,2, Shintaro Sato^1,2, Shuhei Tamate², Yasunobu Nakamura^2,3 (1.Fujitsu, 2.RIKEN, 3.Univ. of Tokyo)

Keywords:quantum computer, qubit, uniformity

Uniformity of Josephson junction (JJ) characteristics is important for high integration of qubits in superconducting quantum computers. The junction resistance (R_N) of the Al/AlO_x/Al JJ was found to be affected by metal deposition on the resist mask sidewall during angled evaporation by simulation using an evaporation model. Furthermore, a two-step evaporation method was introduced to reduce the variation of R_N. The coefficient of variation of R_N was reduced to 4.5% for the 3-inch wafer and 1.1% for the chip.