Title:Design Evolution of MOVPE and HVPE Reactors for Improved Productivity
Speaker:Prof.Dr. Koh Matsumoto
Time：Tuesday,9:30a.m.,11th September
Place：A718
Sponsor：Prof.SUN Qian

Abstact：
In this presentation, challenges and opportunities for MOVPE equipment technology in advanced applications is presented [1]. It would be interesting that the design criteria for nitride MOVPE reactor were found to be very useful for GaAs MOVPE today. Originally, MOVPE reactors for nitrides were developed on the basis of the reactor design for classical III-V materials. Today, the principle of reactor design to cope with the singularity of nitrides brings about essential feedback to the next-generation reactors for classical III-V materials for improved productivity.
At first, we will briefly introduce TAIYO NIPPON SANSO’s technology portfolio as well as an example of international collaborations, followed by design criteria for GaN MOVPE reactor. Secondly, cost analysis of a 15μm-thick GaN layer on a bulk GaN substrate for a vertical electron device is briefly discussed. Since there is a trade-off between a high purity and a high growth rate of GaN, the maximum available growth rate is limited to around 2.5μm/h.
In contrast, for GaAs-based solar cells, the thickness of light absorber is a couple of micrometers, accompanied by a thin (Al)InGaP cap, the growth time of which can be reduced to a few minutes if the growth rate is on the order of a few tens μm/h [2,3].
The next important issue is a discussion of the growth technology on different substrate materials, sapphire, Si, and bulk GaN. In TAIYO NIPPON SANSO, we have been developing THVPE for low cost GaN substrate production. We will briefly introduce the outline of THVPE. Epitaxial cost on a different substrate is discussed in terms of process cycle time, including reactor cleaning. Advantage of a short cycle time on the epitaxial cost will be discussed. GaN on GaN can reduce cycle time because it does not need any buffer layer growth. The cost parity condition of GaN on GaN LED with that on sapphire is discussed. In UVC LED, Prof. Miyake of Mie Univ recently proposed a growth technology of high quality AlN template by high temperature annealing [4]. The possibility of reducing cost of UVC LED by using a high quality AlN template is discussed.

Bio：
Koh Matsumoto was born in Kyoto Japan in Jan.5th, 1954.
He obtained his B.E. and M.S on materials science in 1977 and 1979 from Osaka University, respectively. He obtained PhD degree on MOVPE from Nagoya Institute of Technology in 1996.
He joined TAIYO NIPPON SANSO corp. (NIPPON SANSO at the time) in 1979.
Since late 1982, he has been working on the study of epitaxial growth of compound semiconductors as well as developing reactor.
In Feb. 2008, he was appointed to president of TAIYO NIPPON SANSO CSE (former EMC), which was 100% subsidiary of TAIYO NIPPON SANSO, and was dedicated to design and manufacturing MOVPE tool.
In June 2013, he was appointed to corporate officer division manager of compound semiconductor division of TAIYO NIPPON SANSO, which is dedicated to MOVPE equipment business.
In June 2014, he was appointed to executive corporate officer.
In June 2017, he retired from the executive corporate officer and was appointed to an executive fellow of R&D division to advice MOVPE technology and equipment business.
In 2019, he retired from TAIYO NIPPON SANSO and are continuing to work for the company as contract basis.

Membership: Japanese applied physics society, Japan IEICE, IEEE LEOS, et al.