What is an electrostatic chuck (ESC)?
The ESC is a tool that clamps an object with the force generated between the electrode and the object by applying a voltage to the electrode.
There are two different types of electrostatic clamping methods. One is Coulomb force type that utilizes an insulator as a dielectric material, and the other is Johnson-Rahbek force type that utilizes an attractive force induced by dielectric polarization caused by minute electric current flow across the boundary between an object and a dielectric material.
Differences from the other ESCs
Our electrostatic chucks utilize Coulomb force.
It can realize stable clamping force generated by an opposite charges on an object surface induced by applying a voltage to the electrode.
HPTS, which is an ESC, demonstrates the strongest clamping force under the lowest voltage in ESCs utilizing Coulomb force.
HPTS can generate stable force when the object is an insulator that is known to be difficult to clamp.
Moreover, HPTS never affects on the backside of the object, for example TFT circuit, because electric field does not reach it.
The merits of HPTS
1, Best for clamping thin works because it can apply uniform force to the whole object
2, Clamp various objects such as conductors, semiconductors, insulators and blank glass substrates
3, Never affect on the backside of the object, for example TFT circuit, because electric field does not reach it.
4, Clamp objects with porosity.
5, Give no surface imprints, cracks and transfers of porosity to objects
6, Clamp only one object of the top from a pile of objects
7, Generate a stable clamping force in vacuum environments
8, Generate stronger clamping force under lower voltage than conventional ESCs