Super resolution optical disk mother mold

#This application claims the priority benefit of Taiwanese application serial no. 91107274, filed on Apr. 11, 2002.

#1. Field of the Invention

#The invention relates in general to a super resolution optical disk mother mold, an optical disk stamper, and a fabrication process thereof, and more particularly, to a super resolution optical disk mother mold, an optical disk stamper and the fabrication process thereof that improves the surface roughness of the mother mold and prevents the pre-exposure of the photoresist layer on the mother mold.

#These, as well as other features of the present invention, will become more apparent upon reference to the drawings wherein:

#FIG. 1 shows the process of the conventional optical disk mother mold using a laser beam focused on the photoresist layer directly;

#FIG. 2A shows the process of fabricating an optical disk mother mold using the thermal-induced super resolution process;

#In FIGS. 4A to 4D, a optical disk mother mold fabricated by using a thermal-induced resolution process is shown. Referring to FIG. 4A, a substrate 400 such as a glass substrate or other transparent substrate with good light transmission, proper hardness and nondeforming property is provided. The thickness of the substrate 400 is about 0.2 mm to about 1.2 mm, for example. A thermal-induced super resolution thin film 408 is formed on the substrate 400. The thermal-induced super resolution thin film includes a first dielectric layer 408a, a thermal-induced super resolution thin film 408b and a second dielectric layer 408c, for example. The first dielectric layer 408a is formed on the substrate 400, the thermal-induced super resolution thin film 408b is formed on the first dielectric layer 408a, and the second dielectric layer 408c is formed on the thermal-induced super resolution thin film 408b.

#The material for forming the thermal-induced super resolution thin film 408b includes silver (Ag), vanadium (V), zinc (Zn), germanium (Ge), indium (In), tellurium (Te), antimony (Sb), gallium (Ga), arsenic (As), tin (Sn) or selenium (Se), for example. The material of the first and second dielectric layer 408a and 408c includes silicon oxide (SiO2), silicon nitride (SiNx), zinc sulfide-silicon oxide (ZnS—SiO2), aluminum nitride (AlNx), silicon carbide (SiC), germanium nitride (GeNx), titanium nitride (TiNx), tantalum oxide (TaOx), or yttrium oxide (YOx).

#After forming the thermal-induced super resolution structure 408, a photoresist layer 402 is formed on the thermal-induced super resolution structure 408. The method for forming the photoresist layer 402 includes spin coating, for example. In this embodiment, the sequence for forming the thermal-induced super resolution structure 408 and the photoresist layer 402 is opposite to that of prior art. That is, the photoresist layer 402 is formed after the thermal-induced super resolution structure 408 is formed. Therefore, the photoresist layer 402 is not affected during the sputtering process for forming the thermal-induced super resolution thin film 408b to effectively prevent the photoresist layer 402 from being pre-exposed.