Image sensing chip packaging structure and packaging method

A packaging method for an image sensing chip, comprising:

• providing a wafer comprising a plurality of image sensing chips arranged in an array, wherein each of the plurality of image sensing chips comprises a first surface and a second surface opposite to each other, and the first surface of the image sensing chip is provided with an image sensing region and a contact pad around the image sensing region;
• forming a light shielding layer at a position on the second surface corresponding to the image sensing region;
• forming a through hole on the second surface, wherein the through hole extends to the contact pad;
• forming an electrical connection layer on an inner wall of the through hole and on the second surface, wherein the electrical connection layer is electrically connected with the contact pad;
• forming a solder mask filling the through hole and covering the electrical connection layer, wherein an opening is formed in the solder mask, and the electrical connection layer is exposed at a bottom of the opening;
• forming a guide contact pad in the opening, wherein the guide contact pad covers an inner wall and the bottom of the opening and extends onto the solder mask, and is electrically connected with the electrical connection layer and extends onto an outer surface of the package for the image sensing chip;
• and
• forming a solder bump on the guide contact pad, wherein the solder bump is electrically connected with the guide contact pad.