Device for a laser lift-off method and laser lift-off method

A laser lift-off method for severing an epitaxially grown semiconductor layer sequence from a carrier, comprising:

• providing a semiconductor layer or the semiconductor layer sequence grown epitaxially on the carrier;
• dividing laser radiation into at least two partial beams;
• and
• superimposing the partial beams in an irradiation plane in which a major side of the carrier remote from the semiconductor layer sequence is located,
• wherein an angle between the at least two partial beams at the irradiation plane is at least 1.0°, the carrier has a thickness of 250 μm to 1.5 μm, and intensity modulation of the superimposed partial beams at a growth side of the carrier facing the semiconductor layer sequence is at most 20%, relative to a local envelope of a beam profile of the superimposed partial beams.

A laser lift-off method for severing an epitaxially grown semiconductor layer sequence from a carrier, comprising:

• providing a semiconductor layer or the semiconductor layer sequence grown epitaxially on the carrier;
• dividing laser radiation into at least two partial beams;
• and
• superimposing the partial beams in an irradiation plane in which a major side of the carrier remote from the semiconductor layer sequence is located,
• wherein
• an angle between the at least two partial beams at the irradiation plane is 7.5° to 50° and an angle between the partial beams and a perpendicular of the irradiation plane is 0° to 30°,
• the laser radiation is pulsed laser radiation and a pulse duration of the laser radiation is at most 50 ns,
• an optical path length difference between the partial beams corresponds to at least 0.025 times and at most 0.25 times the pulse duration, and
• an average roughness of the major side of the carrier remote from the semiconductor layer sequence is 0.1 μm to 5.0 μm.

A device for a laser lift-off method for severing at least one layer from a carrier comprising:

• a laser that generates laser radiation;
• and
• at least one beam splitter;
• wherein
• the laser radiation is divided into at least two partial beams by the at least one beam splitter,
• the at least two partial beams are superimposed in an irradiation plane,
• the irradiation plane is provided such that a major side of the carrier remote from the layer is arranged therein, and
• an angle between the at least two partial beams at the irradiation plane is at least 1.0°, and
• the laser radiation is divided by N−1 beam splitters into N partial beams according to a reflectivity R(N) of the Nth beam splitter:
• R(N)=1/(N+1),
• wherein N is an integer of 3 to 8, and the beam splitters are arranged with increasing reflectivity along a beam path towards the irradiation plane.