Patent ID: 7654887
Filing Date: 2010-02-02
Classification: B24B,H01L,Y10T

Abstract:
1. A vacuum chuck comprising: a sucking body comprising a porous ceramic and having a holding surface configured to suck and hold an object; and a sealing body sealing substantially an entire surface of said sucking body, excluding the holding surface and an air sucking hole corresponding portion of the sucking body, wherein when the pore distribution in said sucking body is measured in accordance with a mercury injection method, the average pore diameter is 10 to 40 μm, the ratio of pores having a pore diameter of 0.7 to 1.2 times of said average pore diameter to the total volume of pores is about 75% or more, the ratio of pores having a pore diameter of less than 0.7 times of said average pore diameter to the total volume of pores is about 15% or less, and the ratio of pores having a pore diameter of more than 1.2 times of said average pore diameter to the total volume of pores is about 10% or less.