In Siplus Semiconductor’s wafer grinding machines and polishing machines, there is a core component in direct contact with wafers — Wafer Chuck
(also known as work stage or vacuum chuck). Wafers are vacuum-adsorbed onto the chuck for high-speed rotational grinding. The end face runout and flatness of the chuck directly determine the TTV (Total Thickness Variation) and surface profile of processed wafers.
Whether adopting air bearings or mechanical bearings for the chuck, all core components are procured from top-tier global suppliers. Even with identical chuck parts assembled by different manufacturers, the achieved precision can differ greatly.
Siplus’s core competitiveness lies in a complete precision control system — from design selection and component precision to assembly control and repeated measurement, no compromises are made in every link.
Assembly: Uncompromised Precision, No Over-tolerance Release
Every assembly step verified by indicator measurement data
Wafer chuck assembly is not a simple fastening operation. Assembly engineers follow detailed assembly drawings marked with precision requirements for each key mounting surface. After installing each component, engineers conduct actual measurements with dial indicators or micrometer indicators, and record the measured values in inspection sheets in real time, rather than relying solely on experience or intuition.
A quality supervisor at Siplus stated:
“If the drawing requires a tolerance of 0.01 mm, we must keep the measured value within 0.01 mm. Even a slight deviation of 0.02 mm will not be approved for release.”
"Strict non-release" is not a slogan, but standardized operation
Some equipment manufacturers may believe that the difference between 0.01 mm and 0.02 mm has limited impact on actual processing, and relaxing standards moderately is acceptable.
At Siplus, there is no such thing as “almost enough” — only clear qualification or disqualification. Once out of tolerance, the assembly must be disassembled and reassembled. A joint review by R&D, production and quality teams will be organized to analyze root causes: insufficient part precision, improper assembly techniques, or overly tight design tolerances.
Workpieces are prohibited from flowing to the next process until the review is passed.
This is because micron-level precision relies on zero tolerance for any minor deviation.
Assembly completion is not the end — re-inspection at the finished machine stage
After chuck assembly, it undergoes overall finished machine testing. Quality engineers re-test dynamic parameters including chuck end face runout, radial runout and rotational speed.
“We recheck key points of the previous process in every working procedure.”
Measurements are taken during assembly and reconfirmed at the finished machine stage, ensuring precision is not compromised in subsequent assembly procedures. This multi-round re-inspection mechanism runs through the assembly process of all core components at Siplus.
System: Rigorous Control From Measuring Tools to Complete Equipment
Adopt higher-resolution measuring instruments
To achieve micron-level accuracy judgment, high-precision measuring tools are essential. Siplus’s metrology laboratory is equipped with imported high-precision testing instruments, whose accuracy is an order of magnitude higher than ordinary micrometer indicators.
The higher the resolution of measuring tools, the more reliable the judgment of processing results. Siplus enforces strict assembly standards, and also ensures the “measuring ruler” itself features superior precision.
Rigorous philosophy applied to every component from chuck to complete machine
The precision of one wafer chuck is accumulated from indicator data of more than ten mounting surfaces. A complete equipment contains dozens of similar core parts, including spindles, linear guides, lead screws and vacuum chucks.
Every component follows the same standard workflow:
Design high-precision requirements → Strict manufacturing by suppliers → Full incoming inspection → Point-by-point indicator measurement during assembly → No release without process review → Re-inspection and confirmation at finished product stage.
The overall precision of Siplus equipment does not depend on occasional compliance in a single link, but is an inevitable result of qualified parts, standardized procedures and rigorous measurements at every step.
Superior performance indicators such as TTV ≤ 1μm and surface roughness Ra ≤ 0.1nm are backed by accumulated indicator measurement data, strict enforcement of the “no release for 0.02mm deviation” rule, and technical support from high-precision testing instruments.
Adherence to Micron-level Precision: A Commitment to Customer Yield
Siplus does not promise perfection, but we guarantee:
Every assembly data is recorded, every out-of-tolerance issue is reviewed, and every product release is fully justified.
This is not just a slogan on the wall, but a code of conduct embedded in every Siplus team member’s daily operation.
In the field of semiconductor precision processing, micron-level precision differences will ultimately affect wafer yield.
Siplus’s rigorous attitude toward every wafer chuck and every process is essentially a commitment to customers’ production line stability.
We firmly believe that only by perfecting every detail can every wafer from customers’ production lines stand the test of high-standard processing.