In the microscopic world of semiconductor manufacturing, a "precision dance" at the millimeter and even nanometer level takes place every day. As 12-inch wafers move along the production line, each positioning, handling and calibration can affect the final yield and performance of the chips. In this process, core components such as wafer aligners, wafer handling robots, wafer calibrators and air-bearing rotary shafts are quietly performing a dual variation of "precision" and "stability" - behind them is the exploration path of a Chinese semiconductor equipment company, Huzhou Prim Semiconductor Co., Ltd. (hereinafter referred to as "Prim"), to reconstruct domestic high-end equipment through technological innovation. 

I. Wafer Alignment Stage: The "Stage" for Nanometer-Level Positioning

The wafer alignment stage serves as the "basic stage" for wafer processing in semiconductor manufacturing. Its core mission is to precisely position the wafer within the process chamber or inspection equipment, ensuring that the errors in subsequent processes such as lithography, etching, and deposition are controlled within the nanometer range. Traditional alignment stages mostly use mechanical contact positioning, but in the face of the sub-micron precision requirements of advanced processes below 5nm, the micro-vibration and thermal deformation caused by contact friction have become bottlenecks. 

Prim's wafer alignment stage adopts a "gas floatation + laser interferometry" compound positioning scheme: the stage surface is suspended above the base through gas floatation bearings, supported by a thin gas film of only a few micrometers, eliminating mechanical contact friction. Meanwhile, a multi-wavelength laser interferometer integrated into the stage surface continuously monitors the wafer position, with feedback accuracy reaching 0.1nm. This design not only enhances the repeat positioning accuracy to ±0.5μm (industry average is ±2μm), but also effectively isolates production line vibration noise through the low rigidity characteristic of the gas floatation structure, providing a "zero disturbance" positioning environment for ultra-precision equipment such as lithography machines. 

II. Wafer Handling Robots: The "Flexible Arms" of the Production Line

During the "journey" of wafers from the Front Opening Unified Pod (FOUP) to the process chamber, the handling robot is the busiest "mover". It needs to complete a series of actions such as picking up the wafer, translating, rotating, and placing it in a cleanroom environment. Each step must balance speed and precision - fast handling can improve production line efficiency, while sub-micron repeatable pick-up accuracy directly determines the alignment consistency of the wafer in subsequent processes. 

Prim's wafer handling robot adopts a drive structure of "linear motor + air bearing guide rail": the linear motor provides backlash-free and high-response driving force, while the air bearing guide rail forms uniform support through compressed air, reducing the coefficient of motion friction to the 10⁻⁶ level. The end effector of the robot integrates vacuum adsorption and elastic buffering devices, which not only avoid physical damage to the wafer surface but also adapt to wafers of different thicknesses (300μm to 1000μm). More notably, it features a "visual guidance" function: through the 3D vision camera it is equipped with, the robot can identify minute defects or positional offsets at the wafer edge in real time and dynamically adjust the grasping path, reducing the breakage rate from the traditional 0.1% to below 0.03%. 

III. Wafer Aligner: The "Monitoring Eye" for Full-Process Quality

The wafer aligner serves as the "quality gate" of the production line. Its function is to inspect the position, angle, and flatness of the wafer before and after each critical process to ensure that process deviations remain within a controllable range. With the increase in wafer size (from 8 inches to 12 inches) and the thinning of wafer thickness (such as fan-out wafers in advanced packaging), traditional contact probe alignment has become inadequate. Contact pressure may cause wafer warpage, while non-contact optical detection is disturbed by uneven reflectivity. 

Prim's wafer calibrator innovatively integrates "multi-spectral confocal measurement" and "AI algorithm correction" technologies: By emitting lasers of different wavelengths, the system can simultaneously obtain data on the surface topography, thickness distribution, and material reflectivity of the wafer, avoiding the blind spots of single-wavelength detection. Coupled with its self-developed deep learning algorithm, it can automatically identify and compensate for positioning errors caused by wafer shape changes (such as thermal expansion) or equipment vibration. The calibration efficiency is 40% higher than that of traditional equipment, and the calibration accuracy can reach 0.2 μm (the industry mainstream is 0.5 μm). 

IV. Air Bearing Spindle: The "Heart" of Precision Motion

Among all the aforementioned equipment, the air bearing spindle is the hidden "core technical cornerstone". Whether it is the rotational positioning of the wafer alignment stage, the angle adjustment of the manipulator during pick-and-place operations, or the multi-dimensional detection of the calibrator, all require high-precision spindles to provide stable motion support. Traditional spindles mostly use ball bearings or crossed roller bearings, but they tend to generate vibrations at high speeds and their lifespan is limited by the wear of the lubricating medium, making it difficult to meet the 24-hour continuous operation requirements of semiconductor equipment. 

Prim's air-floatation rotating shaft adopts a dual-redundancy support structure of "static pressure air-floatation + magnetic levitation": static pressure air-floatation supplies gas to the shaft clearance through a precision air pump to form an air film to support the load; magnetic levitation uses electromagnetic force to actively counteract the remaining vibration, keeping the radial runout of the shaft within 0.1 μm (compared to 2-5 μm for traditional bearings). More importantly, the built-in temperature sensor and servo controller can adjust the air film pressure and magnetic field strength in real time to compensate for shaft drift caused by environmental temperature changes (±1℃) or long-term operation, ensuring the rotational repeat positioning accuracy at the 10⁻⁶ level. This "active control + passive support" design enables the air-floatation rotating shaft to have a lifespan exceeding 100,000 hours, making it a key component for the leap towards high-end in domestic semiconductor equipment. 

V. Huzhou Prim: Defining a New Benchmark for Domestic Equipment with "Precision Genes"

In the cleanroom of Huzhou Prim, engineers are fine-tuning the latest generation of wafer manufacturing equipment - systems that integrate self-developed alignment tables, mechanical arms, calibrators, and air-bearing rotation axes. These have been included in the production line verification of leading domestic wafer fabrication plants. As a company dedicated to the research and development of semiconductor precision equipment, Prim's rise is no accident: its core team members come from the Institute of Microelectronics of the Chinese Academy of Sciences and top overseas equipment manufacturers, having been deeply involved in the field of precision motion control for over a decade. The company invests 20% of its annual revenue in R&D, and has cumulatively applied for 87 patents in areas such as air-bearing technology and multi-sensor fusion, including 15 international PCT patents. 

The competitiveness of semiconductor manufacturing ultimately lies in the meticulous control of details, said the technical director of Prim. "Our equipment may not have the most aggressive parameters, but it is definitely the most stable - from the design stage, we simulate the vibration, temperature and cleanliness conditions of the production line to ensure that each piece of equipment can maintain consistent performance under complex working conditions." This pursuit of "industrial-grade reliability" has made Prim's equipment stand out in yield tests: actual data from a 12-inch wafer fab shows that after using Prim's equipment, the alignment deviation in the lithography process was reduced by 30%, and the overall equipment efficiency (OEE) increased by 25%. 

Conclusion: China's Answer to Precision Manufacturing

From a single wafer to a single chip, it is the result of the coordinated operation of countless precision components; from reliance on imports to self-reliance and control, it is an innovation path that requires enduring loneliness. The story of Huzhou Prim is a microcosm of China's semiconductor equipment industry breaking through "chokepoint" technologies - through technological breakthroughs in core components such as air-bearing spindles, and through system integration of alignment stages, mechanical arms, and calibrators, Chinese enterprises are redefining the "precision standards" of global semiconductor manufacturing. When nanometer-level precision is no longer the exclusive label of foreign equipment, what we see is not only a technological breakthrough, but also a firm confidence of an industry in "Made in China".