The PCB Board inner layer of the image from the original position resulting in short phenomenon. The reason is inner layer of copper foil with low peel resistance or poor temperature resistance for line width is too small, pre-pressure is too high, resin dynamic viscosity is small.
How to solve it?
1. Use high quality inner foil.
2.Reduce pre-pressure or replace the adhesive sheet.
3.Adjust the template.
If PCB thickness is inconsistent, you should adjust the thickness, choose the thickness of small copper foil plate, adjust the parallel degree of hot-pressed membrane plate, limiting the degree of freedom of the laminated sheet and try to place the stack in the central area of hot-pressing template.