Hayabusa2 Project Team

Daisuke KOBAYASHI

  (小林 大輔)

Profile Information

Affiliation
Associate Professor, Institute of Space and Astronautical Science, Department of Spacecraft Engineering, Japan Aerospace Exploration Agency
Associate Professor, The Graduate School of Engineering, Department of Electrical Engineering and Information Systems, The University of Tokyo
Degree
D.S.(Mar, 2005, The University of Tokyo)

Researcher number
90415894
ORCID ID
 https://orcid.org/0000-0002-0140-8820
J-GLOBAL ID
200901096574214055
researchmap Member ID
5000089715

External link

Profile

What? I'm studying space electron devices, especially forcusing on semiconductor-chip malfunctions caused by cosmic rays called "soft errors." I run my laboratory as an associate professor at Institute of Space and Astronautical Science (ISAS), Japan Aerospace Exploration Agency (JAXA) and the Department of Electrical Engineering, Graduate School of Engineering, The University of Tokyo. This portal also serves as the website for my laboratory.

How? We conduct experiments to discover new phenomena and perfoming simulations to analyze them, but what we are focusing on most is "modeling," writing phenomena in simple equations. We are now mainly focusing on developing "soft-error reliability equations," consisited of the following three equations.

Why? We use accelerators to reproduce cosmic rays. We expose semiconductor chips to them and examine what happens. This “expose and examine” approach is the standard method and is indispensable, especially for reliability assurance of semicondctor chips. However, accelerators are limited in number, so accelerator tests are extremely valuable. We often repeat tests; for example, “what happens if we lower the voltage fed to semiconductor chips a bit from the earlier experiment?” Although those condition changes are certainly meaningful, I feel it’s a bit waste to repeat almost the same tests over and over in accelerator experiments. If we can describe how each parameter affects the result with simple equations, we can say something about the results much more without actually irradiating chips. We will then be able to use the valuable accelerator time for other purposes. We would also be able to cut down the time to wait for a chance of accelerator testing to inspect chips we just made. Our goal is zero! We’re trying to create "magical" equations that allow us to say, without even one acclerator exposure, “This chip is fine!”


Committee Memberships

 1

Awards

 9

Papers

 47
  • Daisuke Kobayashi, Ayumu Ikuta
    IEEE Transactions on Nuclear Science, 2026  Peer-reviewedLead authorCorresponding author
    Predicting the single-event upset (SEU) rates of semiconductor devices is essential for their deployment in space and terrestrial cosmic-ray environments. Although various SEU-rate equations were derived for this purpose from different approximations of heavy-ion SEU cross-section curves, no previous studies used an exponential function approximation. This study aims to derive an SEU-rate equation from this approximation and evaluate its validity. The derived equation has a simple closed-form comprising only three physically-intuitive parameters. It shows the potential to predict the SEU rates of a device for galactic cosmic-rays (heavy-ion radiation) on the geosynchronous orbit and atmospheric cosmic-rays (neutron radiation) on the ground in a unified manner, simply by replacing a coefficient. Testing the equation with experimental data of devices fabricated in 250 to 7nm technology nodes shows that our equation can predict their SEU rates within a factor of 2 for the galactic cosmic-rays and 3 for the atmospheric cosmic-rays as accurate as the famous Petersen’s figure-of-merit formula. A further exploration of this similarity between our equation and Petersen’s formula indicates that they are not merely similar but rather identical. The current Petersen’s formula relies on heuristic calibrations to enhance its prediction accuracy. These calibrations can be explained through the exponential-function approximation.
  • Daisuke Kobayashi, Masashi Uematsu, Kazuyuki Hirose
    IEEE Transactions on Nuclear Science, 70(4) 707-713, Apr, 2023  Peer-reviewedLead authorCorresponding author
  • Daisuke Kobayashi, Kazuyuki Hirose, Keita Sakamoto, Yuta Tsuchiya, Shogo Okamoto, Shunsuke Baba, Hiroyuki Shindou, Osamu Kawasaki, Takahiro Makino, Takeshi Ohshima
    IEEE Transactions on Nuclear Science, 68(3) 232-240, Mar, 2022  Peer-reviewedLead authorCorresponding author
  • Keita Sakamoto, Masaki Kusano, Takanori Narita, Shigeru Ishii, Kazuyuki Hirose, Shunsuke Baba, Daisuke Kobayashi, Shogo Okamoto, Hiroyuki Shindou, Osamu Kawasaki, Takahiro Makino, Yoshiharu Mori, Daisuke Matuura
    IEEE Transactions on Nuclear Science, 68(6) 1222-1227, 2021  Peer-reviewed

Major Misc.

 6

Major Books and Other Publications

 3

Presentations

 214

Major Teaching Experience

 2

Major Research Projects

 8
  • TBD
    Apr, 2023 - Mar, 2026
    Daisuke Kobayashi, Takahiro Makino

Industrial Property Rights

 5

Major Academic Activities

 18

Media Coverage

 8

● 専任大学名

 1
  • Affiliation (university)
    総合研究大学院大学(SOKENDAI)