Larry E Drafall

Title: Innovations of Larry E Drafall in Monocrystalline Silicon Growth

Introduction

Larry E Drafall is a notable inventor based in St. Charles, MO (US). He has made significant contributions to the field of semiconductor materials, particularly in the growth of monocrystalline silicon ingots. With a total of 4 patents to his name, Drafall's work has advanced the technology used in the semiconductor industry.

Latest Patents

Drafall's latest patents include a crystal puller and method for growing monocrystalline silicon ingots. This innovative crystal puller is designed according to the Czochralski method and features a housing with a crucible that contains molten silicon. The crucible is engineered to have a side wall with a transmittance of at least about 80% across a light wavelength range of about 500 to 2500 nanometers. The pulling mechanism allows for the upward extraction of a growing ingot from the molten silicon. In practice, polycrystalline silicon is introduced into the crucible, which is then heated to create a molten silicon melt. A seed crystal is subsequently brought into contact with the molten silicon, enabling the growth of a monocrystalline silicon ingot.

Another significant patent involves methods for improving the zero dislocation yield of single crystals. This method focuses on reinforcing the crucible used in the Czochralski process to contain molten semiconductor material. The crucible is constructed from vitreous silica and includes a body with a bottom wall and a sidewall formation. Drafall's innovative approach involves depositing devitrification promoters on both the inner and outer surfaces of the crucible, which enhances the uniform dissolution of the inner surface and reduces the release of crystalline silica particulates into the molten semiconductor material.

Career Highlights

Larry E Drafall is currently associated with MEMC Electronic Materials, Inc., where he continues to contribute to advancements in semiconductor technology. His work has been pivotal in enhancing the efficiency and quality of silicon ingot production.

Collaborations

Drafall has collaborated with notable coworkers such as Leon A Allen and Robert M McCutchan, further enriching the innovative environment in which he works.

Conclusion

Larry E Drafall's contributions to the field of semiconductor materials through his patents and innovative methods have significantly impacted the industry. His work continues to pave