electrostatic chuck

Abstract

This article is used, for example, to adsorb a rectangular glass substrate to be subjected to vacuum processing when placed in the vacuum chamber of a vacuum processing apparatus. This article mainly consists of a base plate and a dielectric layer provided on the front surface of the base plate. The dielectric layer consists of a first dielectric layer and a second dielectric layer, which are visible to the naked eye as a difference in color due to the different volume resistivity of their materials. The dielectric layer also has protrusions that extend toward the front side so as to come into contact with the glass substrate, and these protrusions are formed by processing the contact surface with the glass substrate, which are visible to the naked eye as a difference in color. As shown in the reference cross-sectional view and the DD enlarged reference cross-sectional view showing the substrate adsorption state, when a voltage is applied to electrodes provided in the dielectric layer after the glass substrate has been placed on the dielectric layer, the portion of the glass substrate facing the first dielectric layer is adsorbed by a Johnson-Rabec or Coulomb force, and the portion of the glass substrate facing the second dielectric layer is adsorbed by a gradient force. Furthermore, this product is provided with a first gas passage that penetrates the base plate in the thickness direction, and a slit-shaped second gas passage formed in the dielectric layer that communicates with the first gas passage, allowing a predetermined gas to be introduced between the substrate and the gas passage.

Images