Apparatus for etching substrates by a glow discharge

摘要

In an apparatus for etching substrates (18) by a glow discharge in vacuum, containing a vacuum chamber (13), a substrate carrier (17), an electrode (20, 21, 22) and a high-frequency generator (24) which is connected on the one hand to the substrate carrier (17) and on the other hand to the electrode (20, 21, 22, 28), the electrode (20) opposite the substrate carrier (17) and at least partly enclosed by a cup-shaped, earthed screen (23) is provided in the marginal zone with a projection (22) which is at the same potential and bridges the space between the electrode and the substrate (18) or substrate carrier (17) except for a gap, a diaphragm ring (28) being provided at the encircling, bottom margin of the roughly cylindrical projection (22) of the diode (20). The diaphragm ring (28) extends radially to the inside in a plane parallel to the substrate (18). In order to obtain a displacement of the etched marginal trench which occurs during the anode sputtering, the cup-shaped screen (23) has a ring (26) of electrically insulating material which, from its marginal part (29) extending over the projection (22) of the electrode (20), extends radially inwards in a plane parallel to the substrate (18) up close to the outer margin (30) of the substrate (18). <IMAGE>