ESC Basics

ESC Basics – Opposites Attract

For Coulombic type ESC, a high impedance non conducting ESC material is used. We use Alumina (Al2O3) for its excellent dielectric properties and for its durability.

A chucking force P forms between the dielectric layer and the top surface of the wafer when a voltage is applied to the electrode. For a given power supply and chucking voltage, the force P is mainly drive by the dielectric constant and thickness of the top Al2O3 layer of the ESC.

The Coulombic ESC can be monopolar or bipolar. The electrodes are made of some conductive material like Tungsten.

The materials used are critical to the performance and the lifetime of the ESC, as well as the customer process.