[12p-A305-1~13] 13.5 Semiconductor devices/ Interconnect/ Integration technologies

[12p-A305-12] Development of Via-Switch with Multi-Layered a-Si/SiN/a-Si Varistor

〇Noriyuki Iguchi¹, Naoki Banno¹, Koichiro Okamoto¹, Hideaki Numata¹, Masanori Hashimoto², Tadahiko Sugibayashi¹, Toshitsugu Sakamoto¹, Munehiro Tada¹ (1.NEC Corp., 2.Oosaka Univ.)

Keywords:Atom switch, FPGA, Selector

Two-varistors selected complementary atom switch (a.k.a. via-switch) is newly proposed for a nonvolatile, highly-dense and low-power FPGA. A compact via-switch is placed at each cross-point, in which the two control lines connected to the varistors can realize the multiple fan-outs (FOs) without select transistors. In this work, a newly a-Si/SiN/a-Si varistor with a novel triple layered SiN shows superior nonlinearity (NL) of 1.1x10⁵ with maximum current density of 1.63MA/cm². Since we discuss the conducting mechanism of the proposed varistor to improve the NL performance, the effects of composition of the SiN layer are analyzed. We clarify that the improved NL of the a-Si/SiN/a-Si varistor is caused by its staircase barrier height. The via-switch is a strong candidate for switch elements of low-power FPGA.