Patent ID: 7506609

Claim:
An arrangement for generating a local electron-cyclotron microwave resonance (ECR) low pressure plasma at a predeterminable location within a process chamber ( 14 ), the arrangement comprising: a process chamber ( 14 ) with a microwave transparent window ( 12 ), through which a selected gas of a predetermined density n can be introduced into the process chamber, a microwave source ( 1 ), a microwave reflection structure ( 10 ) having a shell-like reflection area with a focal point or line (B) arranged opposite the microwave transparent window ( 12 ), a microwave guide ( 1 ′) extending from the microwave source ( 1 ) to the focal point or line (B) and having an uncoupling opening in the focal point or line (B) for directing the microwaves directly onto the microwave reflection structure ( 10 ), so that a parallel microwave beam ( 13 ) is formed which is directed through the microwave transparent window ( 12 ) into the process chamber ( 14 ), a substrate holder ( 16 ) with a substrate ( 18 ) disposed thereon arranged in the process chamber opposite the microwave transparent window ( 12 ), a magnetic field generating device ( 24 ) including magnets having S- and, respectively N-poles arranged in the process chamber ( 14 ) at opposite sides of the microwave beam ( 13 ) between the substrate holder ( 16 ) and the microwave transparent window ( 12 ) and having a pole axis extending perpendicularly to the microwave beam ( 13 ) whereby the microwave beam ( 13 ) passes through a magnetic field (B 0 ) generated by the magnetic field generating device ( 24 ) and a cross volume ( 26 ) of at least 0.5 cm 3 is formed in which the magnetic field has such a strength, that the input microwave radiation with the excitation frequency ω E is essentially equal to the electron-cyclotron frequency ω EZ so that ECR conditions are established, wherein ω EZ =e 0 /m e ×B 0 , e 0 being the elementary charge and m e being the electron mass so that a plasma of increased density is formed in the cross-volume ( 26 ), the magnetic field generating device ( 24 ) being movable together with the cross volume ( 26 ) in which ECR conditions exist along the microwave beam into direct interactive contact with the substrate ( 18 ).