Yuuji Tsutsumi

Title: Yuuji Tsutsumi: Innovator in Silicon Production

Introduction

Yuuji Tsutsumi is a notable inventor based in Nagasaki, Japan. He has made significant contributions to the field of silicon production, holding a total of 2 patents. His work focuses on innovative methods for producing high-quality monocrystalline silicon, which is essential for various applications in electronics and solar energy.

Latest Patents

Tsutsumi's latest patents include a production method of monocrystalline silicon based on the emissivity of a production apparatus. This method involves measuring the emissivity of the inner wall surface of a top chamber and determining the target resistivity of monocrystalline silicon based on the measured emissivity. The process ensures that when the emissivity is 0.4 or less, the target resistivity is set to be less than 3.0 mΩ·cm when using arsenic as a dopant.

Another significant patent is the n-type silicon single crystal production method. This method involves pulling up a silicon single crystal from a silicon melt containing red phosphorus as a principal dopant. The process controls the electrical resistivity at the start position of the silicon single crystal to be between 0.80 mΩ·cm and 1.05 mΩ·cm, while sequentially lowering the resistivity as the crystal grows.

Career Highlights

Yuuji Tsutsumi is currently employed at Sumco Corporation, a leading company in the silicon wafer industry. His expertise in silicon production has positioned him as a key player in advancing technologies related to semiconductor materials.

Collaborations

Tsutsumi has collaborated with notable colleagues such as Shinichi Kawazoe and Yasuhito Narushima. Their combined efforts contribute to the ongoing innovation in silicon production techniques.

Conclusion

Yuuji Tsutsumi's work in the field of silicon production exemplifies the importance of innovation in technology. His patents reflect a commitment to improving the efficiency and quality of silicon materials, which are vital for modern electronics and renewable energy solutions.