METHOD OF MANUFACTURING MULTILAYER RIGID-ELASTIC PRINTED CIRCUIT BOARD Russian patent published in 2024 - IPC H05K1/02 H05K3/06 H05K3/46 

FIELD: electrical engineering.

SUBSTANCE: invention relates to the field of electrical engineering, namely to a method of producing combined boards, in which rigid parts are connected to each other by an elastic loop. In the manufacturing method, it includes the operations of etching copper foil-clad polyimide by a liquid method and polyimide by a reactive-ionic method to achieve the width of the polyimide paths of meander shape greater than the width of the copper conductors, which contributes to lower mechanical stresses in conducting lines during deformations and necessary limitation of extensibility to preserve their electrical integrity. For high rate of metal etching with minimum lateral undergrowth, solution of 160-240 ml of deionised water, 120-180 ml of hydrogen peroxide, 15-25 g of sulphamic acid and 2.5-4.5 ml of hydrochloric acid is used. Reactive ion etching of polyimide takes place in a medium containing oxygen, argon and SF6 gas with flow rates of 0.9-1.1 l/h, 0.8-1.2 l/h, 0.5-0.6 l/h, respectively, through the copper mask with the help of steel tooling, which provides the clamping force and additional heat removal. After forming the topology of the internal signal layers of the printed circuit board, an elastic train is created by applying and curing an elastic material with thickness of 300-800 mcm and an adhesion activator for a metal of the silane group. Connection of elastic loop with formed meander topology in foil-clad polyimide with rigid parts of board from glass fibre is performed by pressing.

EFFECT: creation of a rigidly elastic printed circuit board with high mechanical resistance to stretching, compression, bending and twisting.

1 cl, 2 dwg