Image sensor having shortened wires

An image sensor to be electrically connected to a printed circuit board, the image sensor comprising:

• a substrate composed of a plurality of metal sheets arranged in a matrix, each of the metal sheets having a first board and a second board located at a height different from that of the first board, and a chamber being defined under a bottom surface of the substrate;
• a photosensitive chip arranged within the chamber;
• a plurality of bonding pads formed on the photosensitive chip at positions corresponding to the first boards of the substrate, the bonding pads and the first boards of the substrate being staggered so that each of the bonding pads is arranged between adjacent two of the first boards;
• a frame layer formed on a periphery and the bottom surface of the substrate to encapsulate the photosensitive chip, upper faces of the first boards and bottom faces of the second boards being exposed out of the frame layer, and the bottom faces of the second boards being electrically connected to the printed circuit board;
• a plurality of wires, each of which having a first terminal and a second terminal, the first terminals being electrically connected to the bonding pads of the photosensitive chip, respectively, and the second terminals being electrically connected to the corresponding staggered first boards of the substrate, respectively;
• and
• a transparent layer placed on the frame layer to cover the photosensitive chip so that the photosensitive chip may receive optical signals passing through the transparent layer.