Milestone-Proposal talk:Thin Film Hall Elements

Advocates’ Checklist (Read Only; Do Not Edit)

1. Is the proposal for an achievement rather than for a person? If the citation includes a person's name, have the proposers provided the required justification for inclusion of the person's name?
2. Was the proposed achievement a significant advance rather than an incremental improvement to an existing technology?
3. Were there prior or contemporary achievements of a similar nature? If so, have they been properly considered in the background information and in the citation?
4. Has the achievement truly led to a functioning, useful, or marketable technology?
5. Is the proposal adequately supported by significant references (minimum of five) such as patents, contemporary newspaper articles, journal articles, or citations to pages in scholarly books? At least one of the references should be from a peer-reviewed scholarly book or journal article. The full text of the material, not just the references, shall be present. If the supporting texts are copyright-encumbered and cannot be posted on the ETHW for intellectual property reasons, the proposers shall email a copy to the History Center so that it can be forwarded to the Advocate. If the Advocate does not consider the supporting references sufficient, the Advocate may ask the proposer(s) for additional ones.
6. Are the scholarly references sufficiently recent?
7. Does the proposed citation explain why the achievement was successful and impactful?
8. Does the proposed citation include important technical aspects of the achievement?
9. Is the proposed citation readable and understandable by the general public?
10. Will the citation be read correctly in the future by only using past tense? Does the citation wording avoid statements that read accurately only at the time that the proposal is written?
11. Does the proposed plaque site fulfill the requirements specified by the Milestones Guidelines? (i.e. publicly accessible, appropriately related to the achievement, secure, etc.)
12. Is the proposal quality comparable to that of IEEE publications?
13. Are any scientific and technical units correct (e.g., km, mm, hertz, etc.)? Are acronyms correct and properly upper-cased or lower-cased? Are the letters in any acronym explained in the title or the citation?
14. Are date formats correct as specified in Section 6 of Milestones Program Guidelines? Helpful Hints on Citations, plaque locations
15. Do the year(s) appearing in the citation fall within the range of the year(s) included at the end of the title?
16. Note that it is the Advocate's responsibility to confirm that the independent reviewers have no conflict of interest (e.g., that they do not work for a company or a team involved in the achievement being proposed, that they have not published with the proposer(s), and have not worked on a project related to the funding of the achievement). An example of a way to check for this would be to search reviewers' publications on IEEE Xplore.
17. Are the GPS coordinates correct and in decimal format?
18. Is the proposed achievement controversial because of various reasons including but not limited to: ecological, environmental, social impact, political scandal, etc.? (A relatively simple Google search on the achievement by the advocate, combined with words such as "protest", "scandal", "environmental impact" should be sufficient to alert the advocate.)

Independent Expert Reviewers’ Checklist

1. Is suggested wording of the Plaque Citation accurate?
2. Is evidence presented in the proposal of sufficient substance and accuracy to support the Plaque Citation?
3. Does proposed milestone represent a significant technical achievement?
4. Were there similar or competing achievements? If so, have the proposers adequately described these and their relationship to the achievement being proposed?
5. Have proposers shown a clear benefit to humanity?

In answering the questions above, the History Committee asks that independent expert reviewers apply a similar level of rigor to that used to peer-review an article, or evaluate a research proposal. Some elaboration is desirable. Of course the Committee would welcome any additional observations that you may have regarding this proposal.

Submission and Approval Log (For staff use only)

Submitted date: 21 August 2025
Advocate approval date:
History Committee approval date:
Board of Directors approval date:

Expert Reviewer's Report_1_Toshiyoshi uploaded by Advocate -- Tomohiro Hase (talk) 02:34, 26 August 2025 (UTC)

2025-08-26

IEEE Milestone Proposal Review for “Thin Film Hall Elements”

Hiroshi Toshiyoshi, Ph.D.
Professor, Institute of Industrial Science, The University of Tokyo

(1) Is suggested wording of the Plaque Citation accurate?

Yes.

(2) Is evidence presented in the proposal of sufficient substance and accuracy to support the Plaque Citation?

Yes. I have reviewed the provided papers and technical notes and found that they support the significance of this invention. I also confirmed that the US translation accurately reflects the original Japanese.

(3) Does proposed milestone represent a significant technical achievement?

Yes. The invention of the thin-film Hall element has contributed to the widespread adoption of brushless motors, which in turn underpins the current boom in electric vehicles. Moreover, the shift to brushless motors has significantly reduced the frequency of failures of motors, allowing for a reduction in the inspection frequency of railway vehicles and other equipment. The resulting economic impact is quite substantial.

(4) Were there similar or competing achievements? If so, have the proposers adequately described these and their relationship to the achievement being proposed?

To the best of my knowledge, I am not aware of any technology related to this invention. As noted in the proposal, there were bulk semiconductor versions of Hall sensors. Compared with the thin-film Hall element developed in this work, those bulk versions were unsuitable for mass production and incompatible with compact packaging.

(5) Have proposers shown a clear benefit to humanity?

Definitely yes. All of today’s factory automation systems, electric vehicle, high-speed trains, flying drones, HDD spindles, and emerging humanoid robots rely on this invention. Simply listing these applications is sufficient to convince people of the historical significance of the thin-film Hall sensors invented in 1983.

Conclusions:
Rotary mechanisms (excluding biological nanomotors) do not exist in nature and were a remarkable invention of humankind. The transformation of rotary mechanisms into a source of power through the steam engine, followed by their replacement with electric motors, was also a significant human achievement. However, no advanced “intelligence” had been introduced into the motor-driven mechatronics before the invention of thin-film Hall elements. This invention should be recognized as a technological heritage of the world.

Expert Reviewer's Report_2_Ishida uploaded by Advocate -- Tomohiro Hase (talk) 06:56, 26 August 2025 (UTC)

In my capacity as Advocate, I am submitting the attached Expert Review Report, which was received on August 26, 2025, from Dr. Makoto Ishida, Professor Emeritus of Toyohashi University of Technology.

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Review Report: Commercialization of Thin Film Hall Elements, 1983

(1) Is suggested wording of the Plaque Citation accurate?

Yes, the proposed inscription is accurate.

(2) Is evidence presented in the proposal of sufficient substance and accuracy to support the Plaque Citation?

Yes, the content described under Historical Significance and its supporting references have been thoroughly reviewed and confirmed.

(3) Does proposed milestone represent a significant technical achievement?

To achieve a thin-film magnetic sensor with high sensitivity and high reliability suitable for industrial applications, they established a proprietary InSb film manufacturing process, developed a sensor structure that achieved enhanced sensitivity, and improved temperature characteristics by an order of magnitude through constant-voltage operation enabled by the high resistance of InSb films. Furthermore, they realized mass production using integrated circuit technology, maintaining the industry's highest shipment volume to date.　These high-sensitivity magnetic sensors enabled the development and mass production of ultra-compact, quiet, and highly precise rotational control motors that were essential for VTRs and personal computers, creating an entirely new generation of motor technology. This innovation also opened an era of virtually unlimited applications for magnetic sensors, driving widespread adoption beyond the electrical and electronics industries into everyday life, academia, technology, culture, and society as a whole.
Asahi Kasei's high-sensitivity Hall element HW Series, which addressed expectations for the future of sensor technology, has become the most widely used magnetic sensor globally, with cumulative shipments exceeding 40 billion units over 40 years since its launch, contributing significantly to the realization of technological advancements. This remarkable social contribution clearly merits recognition as an IEEE Milestone.

(4) Were there similar or competing achievements? If so, have the proposers adequately described these and their relationship to the achievement being proposed?

Prior to this achievement, no thin-film high-sensitivity magnetic sensor existed. The proposer was the first to develop a proprietary vacuum deposition method to grow high-mobility InSb thin films, establish an industrially viable process, and deliver magnetic sensors featuring exceptional sensitivity, outstanding thermal stability, compact size, low power consumption, and scalability for mass production—without any comparable competing technology.
These breakthroughs were made possible through the development of dedicated InSb thin-film growth equipment, optimization of growth conditions, and innovations in sensor device architecture that ensured both high sensitivity and superior thermal stability. Additionally, a robust, high-reliability mass-production system suitable for industrial deployment was successfully established. These achievements represent a level of innovation that is truly without precedent.

(5) Have proposers shown a clear benefit to humanity?

For the first time, a comprehensive development and production system was established to manufacture thin-film magnetic sensor devices suitable for industrial applications, delivering significant benefits to society. The HW Series Hall elements were widely adopted in consumer electronics such as VTRs and personal computers, firmly establishing thin-film Hall elements as practical magnetic sensors and creating a profound impact on the industry. Their application quickly expanded from magnetic sensors for small DC motors in VTRs and floppy disk drives to CD/DVD-ROM drives, resulting in a rapid increase in production.
Furthermore, these sensors were extensively used in cooling fans for personal computers, air conditioners, and servers, contributing to device miniaturization and energy efficiency. In recent years, their application has continued to grow, notably in drive motors for electric tools such as power screwdrivers, enabling miniaturization and battery-powered operation. This continuing expansion of applications remains a remarkable testament to the enduring impact of this technology.

In conclusion, the 'Commercialization of Thin Film Hall Elements, 1983' represents a technological and historical achievement of exceptional value and is strongly recommended for recognition as an IEEE Milestone.

Makoto Ishida, Ph. D.
Professor Emeritus, Toyohashi University of Technology.

Expert Reviewer's Report_3_Kuriyama uploaded by Advocate -- Tomohiro Hase (talk) 06:02, 27 August 2025 (UTC)

I am uploading the following Review Report, which I received today (August 27, 2025) from Professor Kuriyama.
Dr. Tomohiro Hase, IEEE Fellow.
Advocate, IEEE History Committee.

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Review Report: Commercialization of Thin Film Hall Elements, 1983

(1) Is suggested wording of the Plaque Citation accurate?

Yes, the inscription can be regarded as reliable and accurate.

(2) Is evidence presented in the proposal of sufficient substance and accuracy to support the Plaque Citation?

Yes, the content of the above-mentioned inscription has been verified by primary documentary evidence (see [references]), although there are few third-party evaluations such as academic papers.

(3) Does proposed milestone represent a significant technical achievement?

Yes, it can be corroborated that this work (Thin Film Hall Elements) represents a significant technical achievement such as high performance, mass production, and widespread adoption of brushless DC motors.

(4) Were there similar or competing achievements? If so, have the proposers adequately described these and their relationship to the achievement being proposed?

No. To the best of my knowledge, there were no similar or competing achievements. This conclusion is supported by the absence of contemporary records or evidence indicating comparable technical accomplishments.

(5) Have proposers shown a clear benefit to humanity?

Yes, the proposers have demonstrated a clear and tangible benefit to humanity through their technological achievement. The high-sensitivity magnetic sensors allow for more precise motor control, reducing energy loss and improving overall system efficiency.

This technology holds significant value as a technical and historical asset, and therefore deserves strong recommendation as IEEE milestone in human progress.

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Toshihide Kuriyama, Dr.
Japan Society of Next Generation Sensor Technology, Board Member
MarronTech, Owner
Kinki University, former professor
Waseda University, former visiting research scholar
University of Pennsylvania, former visiting research scholar
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