Abstract
Nano-imprint technique has the advantage of high throughput, sub-10nm resolution and low cost. In the printing process, however, the mold deformation often occurs and causes a great concern of the quality of pattern transfer, such as the uniformity. This paper presents a uniform printing method across the wafer by introducing the local mold deformation along the block boundaries. This method is simple and effective with the grooves cut on the backside within the non-patterned area of mold. The grooves lead the mold to lie and to close fit easily on substrate and obtains more uniform pattern on large surface. Both analytical and experimental investigations were conducted to verify the proposed approach. The analytical results reveal that increasing the imprinting force or mold area will cause the substrate distortion and affect the imprinted quality significantly. The grooves can improve the defects and increase the uniform stress distribution in the patterned area. Using the proposed technique to fabricate 50nm grates with the aspect ratio as high as 4 on 4” silicon wafers are successful. The results demonstrate a new imprint method of introducing the controlled local mold deformation for more uniform imprint across large area. This technique enhances the nano-imprint performance in practice.