Matrix printed board and process of forming the same

A process of manufacturing a matrix printed board, comprising the steps of:

• forming a first conductive layer on a substrate by screen printing:
• forming a first insulating layer on said first conductive layer, said first insulating layer having a hole through which an electrical contact portion of said first conductive layer is exposed;
• forming a second insulating layer on said first insulating layer, said second insulating layer having a hole corresponding to the hole in said first insulating layer through which an electrical contact portion of said first conductive layer is exposed, wherein an angle of inclination, with respect to an upper surface of the substrate, of the hole formed by said first insulating layer is greater than an angle of inclination of the hole formed by said second insulating layer;
• and
• forming a second conductive layer on said second insulating layer.