Driving backplane and method for manufacturing the same, and display device

A method for manufacturing a driving backplane, comprising:

• forming a first conductive pattern on a surface of a base substrate, the first conductive pattern comprises a plurality of signal lines;
• forming an insulating layer with a plurality of via holes therein on the base substrate on which the first conductive pattern is formed;
• forming a second conductive pattern on the base substrate on which the insulating layer is formed, the second conductive pattern comprises a plurality of pairs of coupling electrodes, each pair of coupling electrodes being respectively used for coupling two electrodes of a light emitting device;
• each signal line is coupled to at least one of the coupling electrodes through the via hole in the insulating layer;
• sequentially forming an inorganic material layer and an organic material layer on the base substrate on which the second conductive pattern is formed;
• performing a step exposure and development on the organic material layer to form an intermediate pattern;
• the intermediate pattern comprises a hollow-out portion, a completely-reserved portion and a half-reserved portion, and an orthographic projection of the half-reserved portion on the base substrate covers a spacing region between the pair of two coupling electrodes;
• an orthographic projection of the hollow-out portion on the base substrate covers at least a part of the coupling electrode;
• a thickness of the completely-reserved portion is greater than that of the half-reserved portion, and a thickness of the half-reserved portion is x times a thickness of the inorganic material layer;
• etching the inorganic material layer and the intermediate pattern until a portion of the inorganic material layer, corresponding to an area where the hollow-out portion is located, is removed;
• during the etching, an etching selection ratio of the inorganic material layer to the intermediate pattern is 1:y, wherein 0<x≤y.