| 摘要 |
<p>PURPOSE:To control electric potential of a substrate freely while showing normal attraction function by providing a substrate of a conductor or a semiconductor substance on a first electrode with an insulator between and by burying a second electrode which provides it with an electric potential in the insulator. CONSTITUTION:An Mo-made first electrode 61 has an outer diameter and an inner diameter of a large circle of 9cm and 6cm, respectively and a diameter of a small circle of 3cm and a space part of an Mo-made second electrode 63 which provides an electric potential to a substrate 64 is about 1mm. An insulator 62 is formed of 250mum-thick alumina, separated from the second electrode 63 and a periphery is enclosed. When 1kV is applied in air and a 4 inch wafer is attracted, it is attracted completely by a force of 0.2N/cm or more. It becomes possible to control an electric potential of a substrate surface while making a large current flow through a substrate and to attract the substrate by electrostatic force. It is also resistant to thermal stress and is useful when controlling an electric potential at a positive side from self-bias by plasma and when a substrate of a large area is used.</p> |
