Method for structuring thin metal layers. - with a laser beam used for selective removal of such layers.

: Bollmann, D.; Klumpp, A.

Abstract
The method consists of the following steps: (a) provision of a structurable layer (2); (b) production of depressions (3) in this layer; (c) application of a layer (5) of copper, a noble metal or a noble metal alloy; (d) removal of the layer (5), except from the depressions (3). The method is characterised by the fact that removal of the layer (5) takes place by means of a laser beam. Alternatively method includes the following steps: 1) production of a thin layer (7) of copper, a noble metal or noble metal alloy on a substrate; 2) application of a structurable layer (8); 3) structurisation of the layer (8) so that the layer (7) is exposed within certain regions; (4) removal of the layer (7) from these regions. This alternative method is characterised by the fact that the step (4) is carried out with use of a laser beam. USE - In semiconductor technology, for metallisation of integrated circuits. ADVANTAGE - Structurisation with a minimised number of process steps is achievable without use of toxic or expensive chemicals. The process is easily control-able and does not depend on side effects not accessible to easy checks.