Against the backdrop of the global semiconductor industry's accelerated iteration towards 3nm and 2nm advanced processes, the "precision race" in wafer manufacturing has entered a white-hot stage. From lithography, etching to thin film deposition, each process places almost exacting demands on the core components of the equipment - the wafer transfer and positioning system: it must achieve sub-micron positioning accuracy while maintaining nanometer-level stability during high-speed movement; it must be compatible with wafers ranging from 8 inches to 12 inches and even larger sizes, and also cope with complex environments such as vacuum and high temperatures in process chambers. 

In this field, Huzhou Prim Semiconductor Co., Ltd. (hereinafter referred to as "Prim"), a "new force" in China's semiconductor equipment sector, is emerging as a key supplier in the domestic semiconductor precision equipment market by making breakthroughs in core technologies such as wafer transfer systems, wafer loading systems, precision motion stage design, and air-bearing rotary shafts. This company, which has been dedicated to precision motion control technology for over a decade, is using independent innovation as its pen to write a new chapter of high-end domestic equipment on the "micro-nano stage" of semiconductor manufacturing. 

I. Industry Pain Point: The "Micro-Nano Challenge" of Wafer Transfer and Positioning

In semiconductor manufacturing, wafers need to be transferred frequently and precisely between different process equipment (such as lithography machines, etching machines, and thin film deposition equipment), and operations such as alignment and clamping need to be completed within the process chambers. During this process, any minor error (such as positioning deviation or vibration interference) can lead to wafer damage, decreased process uniformity, and even the scrapping of an entire batch of chips. Traditional wafer transfer systems mostly rely on mechanical bearings or air-float guides, but due to material properties and control algorithms, they are prone to mechanical vibration at high speeds (such as ≥500mm/s), and the rotational positioning accuracy is difficult to break through the ±1μm mark. Meanwhile, loading systems often suffer from issues such as wafer warpage and surface particle contamination, resulting in an imbalance between loading and unloading efficiency and yield. 

For 12-inch wafers (with a diameter of 300mm), the surface flatness error needs to be controlled at the nanometer level. Traditional contact transmission not only may scratch the wafers but also cannot meet the precise alignment requirements for multi-chip stacking in advanced packaging (such as CoWoS and Fan-out). Therefore, a non-contact, high-rigidity, and low-vibration precision motion system has become the core breakthrough for the upgrade of semiconductor equipment. 

II. Prim's "Breakthrough Strategy": Full-Chain Innovation from System to Core Components

Since its establishment, Prim has been focusing on the field of semiconductor precision motion control. Its technical route has been centered around the three core goals of "high precision, high speed, and high reliability", forming a complete technical system with wafer transfer systems and wafer loading systems as application carriers, precision motion stage design as the underlying support, and air-bearing rotary shafts as the key breakthrough point. 

(1) Wafer Transfer System: The "Safety Guard" for High-Speed Contactless Transmission

The wafer transfer system serves as a "bridge" connecting different process chambers. Its core task is to transfer wafers from one station to another quickly and without damage in vacuum, clean, or corrosive environments. Prim's transfer system adopts a technical solution of "air bearing support + linear motor direct drive + multi-axis coordinated control": 

Air bearing support: By forming a uniform air film (with a thickness of only a few microns) at the contact interface through high-precision air bearings, mechanical friction is completely eliminated, and motion vibration is reduced to the nanometer level.

Linear motor direct drive: Traditional gearboxes, belts and other transmission mechanisms are eliminated, avoiding backlash and elastic deformation, with positioning repeatability reaching ±0.5μm.

Multi-axis coordinated control: Equipped with self-developed high-response servo controllers, it supports X/Y/Z three-axis linkage, with a maximum movement speed of 1m/s and an acceleration of 10g, meeting the requirements of high-speed process cycles.

This system has been verified in a leading 12-inch advanced etching equipment in a certain wafer factory, with the measured wafer transfer yield increased to 99.99%, and the number of wafers processed per hour (UPH) increased by 30% compared to the previous generation of equipment. 

(2) Wafer Loading System: The Leap from "Loading and Unloading" to "Precision Pre-alignment"

The wafer loading system is not only responsible for loading and unloading wafers but also needs to accurately position the wafers within the process chamber (such as aligning the wafer box marks and adjusting the wafer's level). Traditional loading systems mostly use contact mechanical claws, which are prone to positioning errors due to wafer deformation or particle contamination. Prim's loading system innovatively integrates "visual guidance + air float clamping + active vibration isolation" technologies: 

Visual guidance: Through high-resolution industrial cameras and deep learning algorithms, features such as wafer edges and notches are identified in real time, with positioning accuracy reaching ±2μm.

Air float clamping: A non-contact vacuum adsorption (with uniform adsorption force distribution) and air float support composite design is adopted to avoid mechanical stress damage and suppress wafer micro-vibration simultaneously.

Active vibration isolation: Active air springs and inertial actuators are integrated into the equipment base to isolate the influence of ground vibrations (such as from the operation of workshop equipment) on the loading process, ensuring the stability of the wafer when it is placed into the chamber.

Currently, this system has been applied to a domestic 12-inch logic chip manufacturing line, reducing the wafer loading time from the traditional 15 seconds to 8 seconds, with positioning deviation controlled within ±0.8μm, significantly enhancing the overall efficiency of the production line. 

(3) Precision Motion Stage Design: The Foundation of "Micron-level Accuracy"

Whether it is for transfer or loading, the core performance ultimately depends on the design of the precision motion stage. Prim's motion stage adopts the R&D concept of "ultra-precision mechanical structure + multi-physical field coupling control", breaking through multiple key technologies: 

Structural Optimization: The adoption of an integral granite base (with a thermal expansion coefficient as low as 5×10⁻⁷/℃) and a carbon fiber reinforced composite (CFRP) frame ensures rigidity while minimizing thermal deformation.

Drive and Feedback: Equipped with high-thrust-density linear motors and nanometer-scale grating rulers (with a resolution of 0.1nm), combined with temperature sensors and strain gauges, it can compensate for mechanical thermal drift and stress deformation in real time.

Vibration Suppression: Through finite element analysis (FEA), the modal of the motion stage is optimized to suppress resonance peaks within the 10-1000Hz frequency range, ensuring smoothness during high-speed movement.

Third-party testing has confirmed that the positioning accuracy of Prim Precision Motion Stage reaches ±0.3μm (@300mm travel), with repeatability better than ±0.1μm, reaching the top international level. 

(4) Air-bearing Rotating Shaft: A "Chinese Solution" with Nanometer-level Rotational Precision

In scenarios such as wafer alignment and photolithography mask stages, rotational motion is a crucial component. Traditional rotating shafts rely on mechanical bearings (such as crossed roller bearings), which suffer from significant frictional losses, short lifespans (typically less than 10,000 hours), and weak shock resistance. Prim's air-bearing rotating shaft, featuring a "ring-shaped air film support + active control" design, has completely overturned this situation: 

Air film support: By injecting high-pressure air between the rotating shaft and the bearing housing, a uniform air film (with a thickness of 5-20 μm) is formed to achieve non-contact support, reducing the friction coefficient to the 10⁻⁶ level.

Active control: Integrating high-sensitivity pressure sensors and servo valves, the air volume from each air hole is adjusted in real time to compensate for disturbances such as eccentric loading and tilting, achieving a rotational accuracy of ±0.1 μm (@φ300mm).

Long-life design: The air film has no physical contact, with a theoretical lifespan exceeding 100,000 hours, and requires no lubrication, making it suitable for harsh environments such as vacuum and high temperatures.

This technology has been applied in Prim's independently developed wafer-level bonding equipment, achieving nanometer-level alignment of two 12-inch wafers (alignment accuracy ±0.5 μm), breaking the long-term monopoly in this field by overseas companies. 

III. From "Single Product Breakthrough" to "Ecological Synergy": Prim's Path of Domestic Substitution

Prim's technological breakthrough is not an isolated event. Behind it lies a collaborative innovation model of "university research + industrial demand + policy support". The company's core team comes from institutions such as the Institute of Microelectronics of the Chinese Academy of Sciences and Tsinghua University, as well as international equipment giants like Applied Materials and Tokyo Electron, combining academic depth with industrial experience. During the R&D process, Prim established joint laboratories with domestic wafer fabs such as SMIC and Yangtze Memory Technologies, iteratively improving products based on actual production line demands. At the same time, relying on project support from the National "02 Special Project" and Zhejiang Province's "Sharpshooter Plan", it accelerated the transformation of technological achievements. 

Today, Prim's products have covered the entire process of 8-inch to 12-inch wafer manufacturing. Its customers include leading domestic semiconductor equipment companies such as AMEC and Northern Microelectronics. Some of its products have reached or exceeded the performance of similar overseas equipment, but at a price 30% to 50% lower. The delivery time has been shortened to 3 to 6 months (while overseas equipment usually takes more than 12 months). 

IV. Future Outlook: From "Precision Manufacturing" to "Intelligent Manufacturing"

As semiconductor manufacturing evolves towards "three-dimensional and integrated" development (such as 3D NAND and Chiplet), the requirements for equipment have extended from merely "precision" to "intelligence". Prim has already made plans for the next-generation technologies: 

AI-assisted motion control: Predict crystal deformation and environmental disturbances through machine learning algorithms, dynamically adjust motion parameters, and further enhance positioning accuracy.

Multi-functional integrated platform: Develop an integrated "transfer - load - inspection" device to reduce the number of times wafers are moved between processes and lower the risk of contamination.

New materials and new structures: Explore the application of superconducting materials and piezoelectric ceramics in precision motion stages to break through existing physical limits. 

Conclusion

From the precision parts in the laboratory to the "industrial heart" on the production line, Huzhou Prim Semiconductor has proven in ten years that Chinese semiconductor equipment enterprises can not only "follow" but also "lead". Under the era's proposition of "independent controllability", Prim's story has just begun - when the "Chinese key" of precision motion control opens the "micro-nano door" of semiconductor manufacturing, a more efficient and intelligent future of the semiconductor industry is approaching us.