obtained 10 nm 150 nm mocvd or omvpe from organometallic compounds in similar manner to u s pat no 5 124 278 decomposition of organometallic compounds on the te rich layer at 520 u00b0 c to 550 u00b0 c layer thickness obtained 10 nm 150 nm preferably the thicknesses of the individual layer are in the following ranges te 20 nm 150 nm first material 10 nm 150 nm particularly preferably te 40 nm 100 nm first material 20 nm 100 nm and more particularly preferably te 55 nm 60 nm first material 40 nm 60 nm in this regard the individual layer thicknesses correspond to the stoichiometric ratio of the first material to te to be set in the second material for zinc telluride znte and mercury telluride hgte this is preferably a ratio of 1 1 while for arsenic telluride as 2 te 3 and antimony telluride sb 2 te 3 it is preferably a ratio of 2 3 after producing the first back contact layer the further layers of the back contact sequence of layers are applied as described in the prior art preferably in this case they are preferably molybdenum and ni v layers which can be sputtered for example the method in accordance with the invention therefore produces the first back contact layer as a base layer for the back contact layer stack from the first material and te without having to provide the expensive second material for example sb 2 te 3 in the form of a compound fig1 to fig5 diagrammatically show the sequence of the process steps in accordance with the invention for a first embodiment in which a sb 2 te 3 layer is produced as the first back.