Hiramoto and Kobayashi Laboratory


Hiramoto/Kobayashi Lab is pursuing ultimate performance of silicon devices. Main subjects are classified into two categories:


(1) Scaled Silicon MOS Transistors for VLSI
The research target is "Extended CMOS" in which various functions are integrated on CMOS chips. For realizing Extended CMOS, we are studying ultra-low power silicon transistors [1], random variability of scaled CMOS [2], nano-scale silicon nanowire transistors [3], single electron transistors with new functionality, and their integration technologies. Fig. 1 is a schematic showing the idea of Extended CMOS based on so called More Moore Technologies.

(2) Silicon Power Transistors with high Breakdown Voltage
In the field of power devices, it is still possible to enhance the performance of silicon power transistors. In addition to ideas of scaled IGBT [4] and double-gate IGBT [5], we are developing a new idea of lateral silicon power MOSFETs with extremely low on-resistance [6].

In future, above (1) and (2) will be merged and new integrated power electronics with CMOS/power device will be realized. In our opinion, silicon devices will continue to be the main semiconductor devices in the future advanced IT and zero carbon society.

Fig. 1. A schematic of an idea of Extended CMOS. This figure is published in International Technology Roadmap for Semiconductors (ITRS).

[1] A. Ueda et al., "Ultra-Low Voltage (0.1V) Operation of Vth Self-Adjusting MOSFET and SRAM Cell", VLSI Symposium on Technology, pp. 198 - 199, June, 2014.

[2] T. Mizutani et al, "Analysis of Transistor Characteristics in Distribution Tails beyond ±5.4σ of 11 Billion Transistors", IEDM, pp. 826 - 829, December, 2013.

[3] H. Qiu et al., "Statistical Analyses of Random Telegraph Noise Amplitude in Ultra-Narrow (Deep Sub-10nm) Silicon Nanowire Transistors", Symposium on VLSI Technology, pp. T50 - T51, June, 2017.

[4] T. Saraya et al, "Demonstration of 1200V Scaled IGBTs Driven by 5V Gate Voltage with Superiorly Low Switching Loss", IEDM, pp. 189 - 192, December, 2018.

[5] T. Saraya et al., "3.3 kV Back-Gate-Controlled IGBT (BC-IGBT) Using Manufacturable Double-Side Process Technology", IEDM, pp. 87 - 90, December, 2020.

[6] Patent filed, 2021.