Polishing pad comprising window similar in hardness to polishing layer
AssigneeSK enpulse Co., Ltd.
InventorsSunghoon Yun, Joonsung Ryou, Jang Won Seo, Jaein Ahn
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Abstract
Embodiments relate to a polishing pad, which comprises a window having a hardness similar to that of its polishing layer. Since the polishing pad comprises a window having a hardness and a polishing rate similar to those of its polishing layer, it can produce an effect of preventing scratches on a wafer during a CMP process. In addition, the polishing layer and the window of the polishing pad have a similar rate of change in hardness with respect to temperature, so that they can maintain a similar hardness despite a change in temperature during the CMP process.
Claims7
A polishing pad, which comprises:
- a polishing layer having a penetrating hole;
- and
- a window inserted in the penetrating hole,
- wherein the difference in wet hardness between the window and the polishing layer is 0.1 Shore D to 12 Shore D, and the wet hardness is a surface hardness measured upon immersion in water for 30 minutes,
- wherein the polishing layer is formed from a polishing layer composition that comprises a first urethane-based prepolymer, a curing agent, and a foaming agent;
- and the window is formed from a window composition that comprises a second urethane-based prepolymer and a curing agent, wherein the difference in the content of the unreacted isocyanate groups (NCO) between the first urethane-based prepolymer and the second urethane-based prepolymer is 0.4% by weight to 1.0% by weight, and
- wherein the content of the unreacted isocyanate group (NCO) in the first urethane-based prepolymer is 7.5% by weight to 9.5% by weight;
- and the content of the unreacted isocyanate group (NCO) in the second urethane-based prepolymer is 8.1% by weight to 9.0% by weight.
Dependencies are inferred from the claim text.