Abstract A method of and apparatus for treating elements of circular outline. A vessel is provided with guide grooves which are either straight and parallel to one another or are torus-shaped and concentric with one another. The vessel is mounted for tilting movement about a ball and socket joint and accommodates a bath of etching fluid. Disc-shaped elements to be treated are supported on edge in the respective guide grooves. A motor is mounted below the vessel and its output shaft drives a cam follower having at least one ascending and at least one descending surface portion, and in the case of straight parallel guide grooves two rod-shaped follower members are mounted for sliding movement in axial direction of the motor shaft with their ends resting on the cam disc surface and their upper ends engaging the bottom wall of the vessel so that, when they are shifted in axial direction of the motor output shaft, the vessel is tilted alternately to one side and the opposite side about the ball and socket joint. If the guide grooves are torus-shaped, then three such follower members are used which are circumferentially spaced about the axis at equiangular locations.
A method as defined in claim 1; and guiding said element for rolling for rolling on edge in a straight path.
Claim 2
Dependent Claim
27 words
A method as defined in claim 2 and further comprising the step of periodically reversing the direction of rolling movement of said element in said straight path.
Claim 3
Dependent Claim
34 words
A method as defined in claim 2; further comprising immersing additional semiconductor wafer elements in said bath and effecting rolling movement of said additional elements in additional straight paths paralleling the first-mentioned straight path.
Claim 4
Dependent Claim
20 words
A method as defined in claim 1; and guiding said element for rolling in a torus-shaped path surrounding an axis.
Claim 5
Dependent Claim
28 words
A method as defined in claim 5; and further comprising the step of effecting periodic wobbling movement of said bath and said element immersed therein about said axis.
Claim 6
Dependent Claim
34 words
A method as defined in claim 5; further comprising immersing additional semiconductor wafer elements in said bath and effecting rolling of said additional elements in additional torus-shaped paths coaxial with the first-mentioned torus-shaped path.
Claim 7
Dependent Claim
22 words
A method as defined in claim 1, said bath comprising a mixture composed of nitric acid, hydrofluoric acid and glacial acetic acid.
Claim 8
Dependent Claim
18 words
A method as defined in claim 8; further comprising the addition of a wetting agent to said mixture.
Claim 9
Dependent Claim
14 words
A method as defineD in claim 9, wherein said wetting agent is sodiumlauryl sulfate.
Claim 10
Dependent Claim
20 words
A method as defined in claim 9, wherein 10 ml. wetting agent are added per 600 ml. of said mixture.