In the microscopic world of semiconductor manufacturing, "precision" is the most core competitive dimension - the manufacturing of a 12-inch wafer involves hundreds of processes, and the positioning error of each process must be controlled at the micrometer or even nanometer level. As a key support in this field, the design and innovation of precision motion tables are becoming the technological high ground for equipment manufacturers. Prim Semiconductor Co., LTD. (hereinafter referred to as "Prim"), located in Huzhou, Zhejiang Province, is quietly rewriting the technical logic of precision motion stages with its breakthroughs in the fields of air float rotating shafts, ceramic chip forks and wafer loading systems.

I. Precision Motion Table: The "Micro-Operation Master" of Semiconductor Manufacturing

Precision motion tables are the core actuating components of semiconductor equipment such as photolithography machines, etching machines, and thin film deposition equipment. Their core function is to achieve high-precision positioning and motion control of wafers along the X/Y/Z axes and in the rotation direction. Take the photolithography machine as an example. The wafer stage needs to move synchronously with the mask plate at the nanometer level of precision during the exposure process. Any slight vibration or displacement deviation may cause a short circuit or open circuit in the chip circuit.

Traditional motion tables mostly rely on mechanical ball bearings or magnetic levitation technology. However, the former has the problem of precision attenuation caused by friction and wear, while the latter is sensitive to the magnetic field environment and has higher energy consumption. The R&D team of Prim realized that to meet the demand for "sub-nanometer repeat positioning accuracy" in next-generation semiconductor manufacturing (such as 3nm and below processes), it was necessary to find a solution that combines low friction, high rigidity, and no contact wear characteristics - this is precisely the convergence point of air flotation technology and ceramic materials.

Ii. Air Flotation Rotating Shaft: The Leap from "Contact Friction" to "Air Bearing"

One of Prim's core breakthroughs is its independently developed air flotation rotating shaft technology. The traditional rotating shaft relies on mechanical bearings for support. During high-speed operation, it is prone to generating heat and wear due to friction. However, the air-floating rotating shaft achieves "contactless rotation" by injecting high-pressure gas (usually air or inert gas) into the gap between the shaft and the bearing, forming a stable gas film support.

The design of Prim's air flotation rotating shaft includes three innovative modules:

Multi-level gas distribution structure: Through precisely processed micron-sized pore arrays, uniform gas pressure distribution is achieved, avoiding axial displacement caused by local gas film rupture.

Active feedback control system: Integrating high-precision pneumatic sensors and servo valves, it can monitor the thickness of the gas film in real time (with an accuracy of ±0.1μm), and dynamically adjust the gas supply pressure to compensate for external vibrations or load changes.

Composite ceramic bearing sleeve: Made of silicon nitride (Si3N4) ceramic material, its hardness (Mohs hardness 9) far exceeds that of traditional metal bearings, and it has a low coefficient of thermal expansion, maintaining a stable gas film gap even in high-temperature environments.

Actual test data shows that the radial runout of the air-floating rotating shaft is less than 0.5μm, the rotational accuracy reaches ±0.001°, and its service life is more than 10 times longer than that of traditional mechanical bearings. It has been successfully applied to the wafer alignment module and the lithography machine worktable of Prim.

Iii. Ceramic Fork: The perfect balance of lightweight and high rigidity

In precision motion tables, wafer carrying components (such as wafer forks) need to simultaneously meet the dual contradictory demands of "lightweight" (reducing inertial loads) and "high rigidity" (resisting external vibrations). Prim's solution is to use engineering ceramics (such as alumina or silicon carbide) to manufacture the fork body and achieve a breakthrough in structural performance through topological optimization design.

The key technologies of its ceramic fork include:

Material modification: By adding rare earth oxides (such as Y2O3), the thermal shock resistance and surface finish of ceramics are enhanced, making the surface roughness Ra less than 0.1μm to prevent micro-scratches during wafer loading.

Structural bionic design: Drawing on the mechanical properties of honeycomb structures, a porous support frame is designed inside the fork, which reduces weight while maintaining high bending stiffness (30% higher than traditional metal forks).

Surface functionalization treatment: A diamond-like carbon (DLC) coating was prepared on the wafer fork contact surface by plasma spraying technology, with a friction coefficient as low as 0.05, further reducing the wear risk during the wafer transfer process.

At present, Prim's ceramic chip fork has achieved a repeat positioning accuracy of ±0.2μm for a single loading of 12-inch wafers, and no deformation or cracking has been observed in high and low temperature cycling tests (-40℃ to 150℃), which can meet the strict requirements of extreme environments for extreme ultraviolet lithography (EUV) equipment.

Iv. Wafer Loading System: An Upgrade from "Single-machine Efficiency" to "Full-line Collaboration"

The wafer loading system is a crucial link connecting the front-end transmission equipment with the process chamber. Its design needs to take into account the dual goals of "high-speed transmission" and "precise alignment". Prim's wafer loading system innovatively integrates the air-float rotation axis with the ceramic disc fork and introduces AI visual guidance technology, achieving a leap from "mechanical positioning" to "intelligent collaboration".

The core modules of this system include:

Dual-station air-float turntable: Through two independently controlled air-float rotating axes, it achieves rapid wafer flipping (face change time <3 seconds) and Angle calibration (accuracy ±0.005°), meeting the requirements of double-sided photolithography or etching processes.

Multi-degree-of-freedom ceramic chip fork array: Equipped with 4 sets of independently moving ceramic chip forks, it supports the full process automation of "picking - rotating - placing" wafers, with a maximum loading speed of 15 wafers per minute.

AI visual positioning module: Integrating high-resolution industrial cameras and deep learning algorithms, it can identify the edge position and Angle deviation of the wafer in real time (detection accuracy ±5μm), and automatically compensate through the motion stage control system to avoid efficiency loss caused by manual intervention.

In actual production line applications, Prim's wafer loading system has reduced the equipment's wafer changing time by 40% and lowered the wafer breakage rate to below 0.01%, significantly enhancing the overall efficiency and yield of semiconductor manufacturing.

V. Huzhou Prim: The Leap from Technology Following to Standard Setting

As a high-tech enterprise established only three years ago, the rise of Prim Semiconductor is no accident. Its founding team originated from the Institute of Microelectronics of the Chinese Academy of Sciences. In the early stage, it focused on the research and development of precision motion control algorithms, and later gradually extended to the field of core components. Through vertical integration in air flotation technology, ceramic materials and motion control systems, Prim has developed a full-chain capability of "design - manufacturing - testing", and has participated in the formulation of two industry standards (Technical Specification for Air Flotation Bearings for Semiconductor Equipment "and Reliability Test Method for Wafer Loading Systems).

At present, Prim's products have entered the supply chains of leading domestic semiconductor equipment manufacturers and have been exported to overseas markets such as South Korea and Singapore. Its latest research and development direction is the ultra-high precision motion stage for the third-generation semiconductors (such as silicon carbide and gallium nitride), with the target positioning accuracy improved to ±0.05μm, providing stronger technical support for the next-generation chip manufacturing.

Conclusion

From the low-friction movement of the air-float rotation shaft to the lightweight load-bearing of the ceramic chip fork, from the intelligent coordination of the wafer loading system to the overall design of the precision motion table, Prim Semiconductor is redefining the precision boundaries of semiconductor manufacturing with technological innovation. Today, as Moore's Law gradually approaches its physical limit, these seemingly minor advancements in components might precisely be the key force driving the continuous leap in chip performance - after all, in the nanoscale world, the precision of each part determines the future of the entire industry.