In semiconductor manufacturing, the photolithography machine is a key device that determines the precision of chips, and the granite base, with its multiple characteristics, has become an indispensable component of the photolithography machine.
Thermal stability: The "Shield" against Temperature Changes
When a photolithography machine is in operation, it generates a large amount of heat. Even a temperature fluctuation of only 0.1℃ may cause deformation of the equipment components and affect the photolithography accuracy. The coefficient of thermal expansion of granite is extremely low, only 4-8 ×10⁻⁶/℃, which is approximately 1/3 of that of steel and 1/5 of that of aluminum alloy. This enables the granite base to maintain dimensional stability when the photolithography machine operates for a long time or when the environmental temperature changes, ensuring the precise positioning of optical components and mechanical structures.
Super anti-vibration performance: The "sponge" that absorbs vibration
In a semiconductor factory, the operation of surrounding equipment and the movement of people can all generate vibrations. Granite has a high density and a hard texture, and it has excellent damping properties, with a damping ratio 2 to 5 times that of metals. When external vibrations are transmitted to the granite base, the friction between the internal mineral crystals converts the vibration energy into heat energy for dissipation, which can significantly reduce the vibration in a short time, allowing the photolithography machine to quickly restore stability and avoid blurring or misalignment of the photolithography pattern due to vibration.
Chemical stability: The "Guardian" of a Clean Environment
The interior of a photolithography machine comes into contact with various chemical media, and ordinary metal materials are prone to corrosion or the release of particles. Granite is composed of minerals such as quartz and feldspar. It has stable chemical properties and strong corrosion resistance. After being soaked in acid and alkali solutions, the surface corrosion is extremely small. Meanwhile, its dense structure generates almost no debris or dust, meeting the requirements of the highest cleanroom standards and reducing the risk of wafer contamination.
Processing adaptability: The "ideal material" for creating precise benchmarks
The core components of the photolithography machine need to be installed on a high-precision reference surface. The internal structure of granite is uniform and it is easy to be processed to extremely high precision through grinding, polishing and other techniques. Its flatness can reach ≤0.5μm/m, and the surface roughness Ra is ≤0.05μm, providing a precise installation basis for components such as optical lenses.
Long lifespan and maintenance-free: The "sharp tools" for cost reduction
Compared with metal materials that are prone to fatigue and cracking over long-term use, granite hardly undergoes plastic deformation or fracture under normal loads, and it does not require surface treatment, thus avoiding the risk of coating peeling and contamination. In practical applications, after being used for many years, the key performance indicators of the granite base can still remain stable, reducing the operation and maintenance costs of the equipment.
From thermal stability, vibration resistance to chemical inertness, the multiple characteristics of the granite base perfectly meet the requirements of the photolithography machine. As the chip manufacturing process continues to develop towards higher precision, granite bases will continue to play an irreplaceable role in the field of semiconductor manufacturing.
Post time: May-20-2025