LIFT-OFF PHOTOLITHOGRAPHY METHOD Russian patent published in 2017 - IPC H01L21/27 H01L21/312 G03F7/22 H05K3/06 

FIELD: photography.

SUBSTANCE: invention relates to lift-off photolithography and can be used, when obtaining of a working pattern from active material (metal or semiconductor) by selective chemical or plasma-chemical etching via a photoresist mask is difficult or inappropriate due to high chemical resistance to etching of the active material. Disclosed is a lift-off photolithography method, comprising application of polymer photoresist layer on the substrate and its drying, selective exposure of the photoresist layer, obtaining, by development and drying, the photoresist mask with an image, reverse relative to the working pattern, applying, under high-temperature conditions, a layer of active material on the whole surface of the substrate and formed photoresist mask with subsequent removal of the photoresist mask with applied layer of active material, by dissolving the polymer photoresist, located under the layer of active material, the dissolving the polymer photoresist is accompanied by its swelling and forming of the working pattern from the remaining layer of active material applied on the substrate surface. To ensure high-temperature shape stability and heat resistance of the photoresist mask in the initial polymer photoresist, made of phenol-formaldehyde resin and derivative orthonaphthoquinone diazide, additive of a polyhydroxyl-containing compound, selected from glycerine and polyethylene glycol with a molecular weight from 380 to 650 units, is being introduced in amount of 1–11 % of weight of the derivative orthonaphthoquinone diazide.

EFFECT: technical result is increased efficiency of lift-off photolithography due to improving its technological effectiveness.

3 cl, 10 tbl, 2 ex