Method for reducing electrical mutual disturbance of image sensor

The invention discloses a method for reducing electrical mutual disturbance of an image sensor, which comprises the following steps: before the back thinning process in manufacturing process of the image sensor preparation, depositing a stress layer with a certain tensile stress, allowing the stress layer to be subjected to annealing process, plasma or ultraviolet repair process to obtain larger tensile stress, and applying the tensile stress to a substrate, an epilayer and a transistor. According to the invention, the problem that the response speed of a photodiode is affected due to slower electric transfer caused by STI (Shallow Trench Isolation) compressive stress in the prior art is solved, and meanwhile, the problem that as the compressive stress on the epilayer causes electron mobility to be reduced, and electrical mutual disturbance is generated during second illumination in the prior art is solved, the incidence of electrical mutual disturbance problem is reduced, and the image sensor yield is improv