Deeply cultivating semiconductor precision alignment: the core technical path of wafer calibration at Huzhou Pulim

In the entire semiconductor manufacturing process, high-precision positioning and alignment of wafers constitute the core fundamental link that determines chip yield. From lithography, etching, to thin film deposition, advanced packaging, and other processes, stable and reliable precision alignment equipment support is indispensable. Huzhou Pulim Semiconductor Co., Ltd., located in Xihu Science and Technology Innovation Park, Si'an Town, Changxing County, Huzhou City, Zhejiang Province, is a high-tech enterprise focusing on the research, development, production, and technical services of semiconductor-specific equipment. Since its establishment, it has continuously delved into core technologies related to wafer alignment, gradually building a product system that covers multiple scenario needs.

As a crucial auxiliary equipment in the semiconductor manufacturing process, the core function of a wafer aligner is to swiftly accomplish wafer center positioning, eccentricity correction, and notch/flat edge angle alignment before the wafer enters the high-precision processing stage, thereby providing a standardized initial posture for subsequent processes such as lithography and bonding. Traditional manual alignment methods are not only inefficient but also prone to introducing particle contamination due to manual operation, which can affect the clean room environment and product yield. In contrast, automated wafer aligners, by integrating high-performance optical sensors and precision motion control modules, can complete contour detection of wafers ranging from 75mm to 300mm in size within seconds. The alignment accuracy can be stably controlled at a level of positional deviation ≤±0.1mm and angular deviation ≤±0.1°. Additionally, these aligners are compatible with wafers made of various materials such as silicon, silicon carbide, and aluminum nitride, meeting the adaptation needs of different processes in the front-end and back-end of semiconductor manufacturing.

One of the core components supporting the ultra-high precision operation of wafer aligners is the air-bearing rotary shaft. Compared to traditional mechanical contact rotary structures, the air-bearing rotary shaft achieves non-contact suspension support by forming a uniform gas film between the moving and fixed components. This fundamentally eliminates wear, vibration, and accuracy drift issues caused by mechanical friction. It can maintain extremely high rotational stability and repeatable positioning accuracy during long-term continuous operation, fully adapting to the stringent requirements of semiconductor clean production environments. It avoids micro-particle contamination of the wafer surface caused by friction, providing a stable motion foundation for the alignment needs of nanoscale process nodes.

In the core load-bearing and positioning structure of wafer alignment stages, ceramic fork blades are indispensable key functional components. Ceramic fork blades made of high-purity alumina or silicon carbide ceramic materials exhibit excellent characteristics such as high rigidity, low deformation, corrosion resistance, and anti-static properties. During wafer transmission and positioning, they can provide sufficient support strength to avoid wafer warping and deformation, while also reducing the contact area through special surface treatment processes to minimize the risk of wafer surface scratches and electrostatic damage. They fully comply with the cleanliness protection and ESD electrostatic protection standards for semiconductor manufacturing and are widely used in various workstations such as wafer pre-alignment, transmission, and load-bearing.

Based on core precision components such as air-bearing rotary axes and ceramic fork chips, and integrating mature alignment algorithms and optical detection capabilities of wafer aligners, the final formed wafer alignment stage serves as the core carrier for achieving high-precision overlay of mask and wafer multilayer patterns. This type of alignment stage can complete the entire process of mask pre-alignment, wafer pre-alignment, and dual-stage collaborative alignment, with an alignment accuracy that can reach 1/7 to 1/10 of the finest line width dimension. It is fully compatible with production needs at different process nodes ranging from the micrometer level to the nanometer level, and has broad application space in scenarios such as advanced packaging wafer bonding, MEMS device processing, and micro-nano optical element manufacturing.

Relying on its technological accumulation in the field of semiconductor-specific equipment, Huzhou Pulim Semiconductor has deeply integrated the research, development, and production of core products such as wafer aligners, air-bearing rotary axes, ceramic wafer forks, and wafer alignment stages. This integration has enabled it to cover the entire chain from self-research of core components to complete machine assembly and debugging. It can provide highly adaptable precision alignment solutions for semiconductor manufacturing enterprises, helping domestic semiconductor production lines improve process stability and production yield, and contributing solid technical strength to the localization process in the field of semiconductor precision manufacturing.