Performance assessment of ultrathin sapphire wafer polishing with layer stacked clamping (LSC) method

Abstract

Ultrathin sapphire wafer is of great signi cance in the semiconductor eld. In order to explore the effective clamping method of ultrathin sapphire wafer in double-side polishing, this paper studied the characteristic of Layer stacked clamping (LSC) method on polishing ultrathin sapphire wafer with doubleside polishing machine. A self-made friction force test platform was built for learning the friction force between sapphire wafer and baseplate with different baseplate (stainless steel, cast iron, aluminum alloy) and different baseplate surface roughness (R a 3.6 nm, 68.2 nm, 210.1 nm, 517.9 nm). Single factor polishing experiments were carried out on baseplate with different atness (PV value 5.3 µm, 9.8 µm, 19.9 µm, 29.7 µm) and different thicknesses (0.082 mm, 0.104 mm, 0.119 mm). The double-side polishing experiments were carried out to compare the polishing performance on the ultrathin sapphire polishing between LSC method and traditional para n bonding method. The results show that the friction force of stainless steel and iron increase under the adsorption of droplets. Stainless steel performs higher friction force and is more suitable for making the baseplate. The inner fringe of limiter was cut off by the edge of the sapphire wafer and a slope was thereby formed. According to polishing results, LSC method has higher processing e ciency per unit time. The surface roughness, atness and material removal rate are better than para n bonding. Finally, a smooth surface with surface roughness (R a ) 1.3 nm and atness (PV) 0.988 µm was obtained with LSC method.

Molecular Dynamics Analysis of Adhesive Forces between Silicon Wafer and Substrate in Microarray Adhesion

“…Additionally, Chen and others proposed a stacked clamping method, establishing a numerical model based on fractal theory and experimentally verifying the model's effectiveness [17]. They also experimentally validated the polishing performance of stacked clamping [18] and studied the failure mode of limit pieces, attributing it to edge cutting causing the fracture of limit pieces [19]. The clamping mechanism of stacked clamping was investigated, analyzing the adhesive forces between the substrate and the workpiece.…”