Thermal deformation is a core challenge affecting precision and reliability in the manufacturing of semiconductor industry parts. Because semiconductor industry parts require extremely high dimensional accuracy, surface roughness, and structural stability, even minor thermal deformation during processing can lead to part performance degradation or even failure. Therefore, a comprehensive prevention and control system must be established across multiple dimensions, encompassing material selection, process design, thermal management, clamping techniques, and process path planning.
Material selection is the primary step in controlling thermal deformation. Semiconductor industry parts often use materials with significantly different thermal expansion coefficients, such as silicon and gallium arsenide. Therefore, auxiliary materials with similar characteristics must be matched to the processing process. For example, during wafer dicing or photolithography, if the thermal expansion coefficients of the substrate and fixture differ significantly, temperature fluctuations can cause stress concentration, leading to wafer warping or cracking. Choosing ceramics or silicon carbide with low thermal expansion coefficients as fixture materials can significantly reduce deformation caused by improper thermal matching. Furthermore, a layered design of composite materials can improve stability by distributing thermal stress.
Process optimization is a key approach to reducing heat accumulation. In traditional machining, cutting forces and frictional heat are the primary sources of heat, while the semiconductor industry relies more heavily on non-contact technologies such as high-precision etching and laser cutting. Plasma etching, for example, removes material through ion bombardment. While this avoids mechanical contact, the reaction between the plasma and the workpiece surface still releases heat. In this case, pulsed energy input, instead of continuous processing, removes heat through gas cooling or workpiece self-cooling between pulses, thereby keeping temperature rise within the material's deformation threshold.
The design of the thermal management system directly impacts the efficiency of heat removal. During the precision grinding or polishing of semiconductor parts, traditional coolants can cause localized overheating due to insufficient fluidity. To address this, the industry has developed microchannel cooling technology. By embedding micron-sized channels within the machining tool or workpiece, the coolant circulates in a turbulent state, significantly enhancing convective heat transfer. Furthermore, nanofluid coolants are becoming increasingly popular. By dispersing nanoparticles within a base fluid, they significantly improve thermal conductivity and achieve efficient heat dissipation at lower flow rates.
Improving clamping technology is an effective way to prevent thermal stress concentration. During the processing of semiconductor industry parts, traditional mechanical clamping can easily lead to localized stress concentrations, exacerbating the risk of thermal deformation. Replacing mechanical clamping with vacuum or magnetic chucks can reduce localized deformation by evenly distributing the suction force. For thin-walled or irregularly shaped parts, contoured support fixtures can increase part rigidity and prevent deformation caused by vibration or gravity during processing. Furthermore, multi-point flexible clamping technology can further reduce uneven stress distribution caused by clamping by applying uniform force.
Processing path planning also affects the degree of thermal deformation. In multi-axis machining, continuous cutting can lead to localized heat accumulation. Using a skipped machining path, which alternates machining different areas, allows sufficient time for heat to dissipate. For example, in micro-hole machining for 3D packaging substrates, programmable control allows the drill bit to jump between adjacent holes to avoid repeated heating in the same area, thereby reducing material fatigue and deformation caused by thermal cycling.
Real-time monitoring and closed-loop control technologies provide dynamic protection against thermal deformation. By integrating infrared thermal imaging cameras or fiber Bragg grating sensors into processing equipment, real-time temperature distribution data on the workpiece surface can be acquired. Incorporating machine learning algorithms, the system can predict thermal deformation trends and automatically adjust machining parameters, such as reducing spindle speed, increasing coolant flow, or pausing processing for forced cooling. This intelligent thermal management approach shifts semiconductor parts processing from reactive response to proactive prevention.
Controlling thermal deformation in semiconductor parts processing is a systematic project involving materials, processes, equipment, and control. From the selection of low-thermal expansion materials to breakthroughs in microchannel cooling technology, from temperature field homogenization design to intelligent optimization of machining paths, each technological advancement reflects the industry's pursuit of the ultimate in precision. As emerging fields such as 5G and artificial intelligence continue to demand higher performance from semiconductors, thermal deformation control technology will continue to evolve, laying a solid foundation for the industry's advancement towards higher precision and reliability.
