In the field of semiconductor equipment manufacturing, polysilicon gate rings are key components in the chip manufacturing process. When promoting the localization of core components, a domestic semiconductor equipment manufacturer encountered a difficult processing problem - it was necessary to complete high-precision inner contour grinding and groove processing on polysilicon rings with a diameter of 290mm and a thickness of 45mm, and traditional processes were difficult to meet mass production needs.
Processing background and industry pain points
A. Processing background
Due to its excellent semiconductor properties, polysilicon is widely used in gate structural parts of equipment such as ion implanters and etchers. Such components need to remove more than 70% of the material through multiple grinding processes, while ensuring that the inner contour roundness is ≤0.005mm and the groove width tolerance is ±0.01mm, which places strict requirements on the stability of the processing equipment and the life of the tool.
B. Dilemma of traditional processing
1. Traditional grinding machines have low processing efficiency, and a single piece takes more than 8 hours
2. The chipping rate during slot processing is as high as 35%, resulting in batch scrapping
3. The inner circle roundness deviation is > 0.015mm, which affects the uniformity of the equipment plasma distribution
MID Solutions: Ultrasonic technology + high-speed turntable collaborative operation
In view of the processing characteristics of polysilicon hard and brittle materials, the MID technical team customized a three-in-one solution:
1. Ultrasonic precision engraving and milling system: 20kHz high-frequency vibration reduces cutting resistance by 50%
2. DDR vertical high-speed turntable: 3000rpm±1″ precision, achieving nano-level trajectory control
3. Gradient composite tool solution:
Diamond-coated tools are used for rapid material removal during rough processing
Ultrasonic PCD tools are switched for fine processing
Measured data refreshes the industry benchmark
In the customer production line verification, the MID solution achieved:
Processing efficiency increased by 2.8 times, and the processing time of a single piece was compressed to 2.8 hours
The chipping rate of the slot was reduced from 35% to 0.5 % or less
The inner circle roundness is stably controlled at 0.003-0.005mm
The surface roughness Ra≤0.4μm, which is better than the processing level of imported equipment
This breakthrough has increased the mass production qualification rate of customers' polysilicon gate rings from 61% to 98.7%, successfully replacing imported parts.
About MID
MID has been deeply involved in the field of precision manufacturing for more than ten years, focusing on solving the "neck-stuck" processing problems in the semiconductor, photovoltaic and other industries. The company's 7,500 square meters of smart factory is equipped with core technology modules such as ultrasonic assisted processing and five-axis linkage. It has provided key parts processing solutions for more than 20 domestic semiconductor equipment manufacturers. The relevant technologies have passed ISO9001 and semiconductor equipment special certification, and continue to help the process of high-end manufacturing equipment independence.
