Method of removing layered material of a layered construction with a laser beam, with a preliminary grooving step and a removing step

摘要

The method for removing a layer material of a layer structure on a carrier substrate (1) in an actual removal line area, where the layer structure has lower and upper electrically conductive layers (2, 8) and a single- or multi-layered intermediate layer material, comprises introducing an auxiliary trench in the layer material along two opposing sides of the actual removal line area using a laser beam in an auxiliary step, and irradiating the laser beam on the layer material in the actual removal line area laterally next to the auxiliary trench in a removal step. The method for removing a layer material of a layer structure on a carrier substrate (1) in an actual removal line area, where the layer structure has lower and upper electrically conductive layers (2, 8) and a single- or multi-layered intermediate layer material, comprises introducing an auxiliary trench in the layer material along two opposing sides of the actual removal line area using a laser beam in an auxiliary step, and irradiating the laser beam on the layer material in the actual removal line area laterally next to the auxiliary trench in a removal step, so that the layer material present in the actual removal line area is removed in the thickness of the upper electrically conductive layer, where the layer material is removed up to the carrier substrate through the removal step and/or the auxiliary trench is introduced with a predetermined lateral distance (A) from the actual removal line area and acts as a breaking line in the removal step for electrically insulatingly breaking-off the layer material of the upper electrically conductive layer in the area laterally between the auxiliary trench and the actual removal line area using the laser beam. The auxiliary trench is introduced up to a depth, which is smaller than a removal depth of the layer material in the actual removal line area during the removal step. The laser beam differs itself with respect to the wavelength, power density and/or pulse duration of the laser beam during the removal step. The upper electrically conductive layer is a front contact layer of a photovoltaic-multilayer structure on the carrier substrate and the actual removal line area is an isolation trench, which is introduced through the front contact layer. The actual removal line area is an area of the photovoltaic-multilayer structure from which the layer is to be removed, on the carrier substrate, where the single- or multi-layered intermediate layer material contains an absorber layer (6) of the photovoltaic-multilayer structure. The laser beam is irradiated from the back side of the carrier substrate in the removal step, and is irradiated with a wavelength, which is selectively chosen for absorption through the absorber layer. The laser beam in the auxiliary step is selectively chosen for absorption through the front contact layer.