Method of making a backlight module for a printed circuit board

A manufacturing method for a printed circuit board of a backlight module, wherein the printed circuit board comprising an aluminum layer on which a dielectric layer having a predetermined thickness is formed, the dielectric layer comprising a surface on which a conductive layer is formed, the method comprising the following steps:

• (1) etching and patterning the conductive layer on a light bar region of the circuit board on which a light bar is mounted to form a conductive circuit for supplying power to the light bar and etching the conductive layer on a heat dissipating region of the circuit board used for heat dissipation to remove at least a part of the conductive layer of the heat dissipating region of the circuit board;
• and
• (2) cutting a connection location between the light bar region and the heat dissipating region to form a cutting slot, wherein the cutting slot is extended partly into the thickness of the dielectric layer in such a way as not to reach the aluminum layer in order to completely separate and isolate the conductive layer of the light bar region from the conductive layer of the heat dissipating region to prevent short-circuiting between the heat dissipating region and the conductive circuit of the light bar region;
• wherein the printed circuit board has an L-shaped configuration having a first portion comprising the light bar region and a part of the heat dissipating region and a second portion adapted to be fixed to an external fixture for supporting the light bar mounted to the light bar region in position.