SU890572A1

SU890572A1 - Method of chemical processing of printed circuit board

Info

Publication number: SU890572A1
Application number: SU752107170A
Authority: SU
Inventors: Владимир Георгиевич Шульгин
Original assignee: Предприятие П/Я А-7284
Priority date: 1975-02-24
Filing date: 1975-02-24
Publication date: 1981-12-15

Description

(З) СПОСОБ ХИМИЧЕСКОЙ. ОБРАБОТКИ ПЕЧАТНОЙ ПЛАТЫ(3) CHEMICAL METHOD. PCB HANDLING

II

Изобретение относитс к области из готовлени печатных плат, в частное-ти к способам химической обработки, и может быть использовано дл металлизации отверстий печатных плат.The invention relates to the field of the preparation of printed circuit boards, in particular to methods of chemical treatment, and can be used to metallize the holes of printed circuit boards.

Известен способ металлизации отверстий , в котором осуществл ют прокачивание электролита, через отверсти платы в направлении, перпендикул рном плоскости платы 1 .There is a known method of metallization of holes, in which electrolyte is pumped through the holes of the board in a direction perpendicular to the plane of the board 1.

Однако при обработке в в зких растворах , а также при малых диаметрах отверстий в плате обмен растворов происходит с недостаточной интенсивностью и неравномерно, что приводит к снижению качества химической металлизации в отверсти х (разрывы покрыти , слабое сцепление с диэлектриком ) .However, when processing in viscous solutions, as well as with small diameters of the holes in the board, the exchange of solutions occurs with insufficient intensity and unevenly, which leads to a decrease in the quality of chemical metallization in the holes (coating breaks, weak adhesion to the dielectric).

Известен также способ химической обработки печатной платы, включающий принудительную подачу рабочего раствора в зону обработки платы с дросселированием и реверсированием потока1:2 .There is also known a method of chemical processing of a printed circuit board, including the forced supply of a working solution to the board's treatment area with throttling and reversing a 1: 2 flow.

Однако при обработке печатных плат из гибкого диэлектрика неравномерное прокачивание раствора вызыва ет их изгиб, что снижает возможную интенсивность обмена раствора в отверсти х .However, when processing printed circuit boards from a flexible dielectric, uneven pumping of the solution causes their bending, which reduces the possible rate of exchange of the solution in the holes.

Цель изобретени - повышение качества обработки плат.The purpose of the invention is to improve the quality of processing boards.

10ten

Поставленна цель достигаетс тем, что в способе химической обработки печатной платы, включающем принудительную подачу рабочего раствора в зону обработки платы с дросселиро15 ванием и реверсированием потока, поток рабочего раствора- дросселируют по всей поверхности платы, при afoM создают одновременное повышение давлени с одной стороны платы и разрежение с The goal is achieved by the fact that in the method of chemical processing of a printed circuit board, including the forced supply of the working solution to the board processing area with throttling and reversing flow, the working solution flow is throttled over the entire surface of the board, with afoM creating a simultaneous pressure increase from one side of the board and vacuum with

Claims

20 is different at a solution flow pressure of 0.05-0.3 kg / cm, and reversing is performed with a frequency of 10-60 cycles per minute. PRI m e p. A printed circuit board is placed with a thickness of up to 1.6 mm and a hole diameter of 0.4-0.6 mm in a solution of chemical copper plating in a bath between two planes of the cavities through which forced solution is supplied. A cavity plate is placed in the bath below the level of the solution. The planes of the cavities are located opposite each other at a distance of mm and are made in the form of cells with holes n the center of these cells, with the cells of one plane displaced relative to the cells of the other plane by half their size. Each of the cavities has a fitting for connection to the pipelines for reversing the solution. When applying the working solution, an overpressure of the solution is simultaneously created, for example, in the first cavity of the board 0.05-0.3 kg / cm (determined by the diameter and number of holes) and vacuum in the other by forcibly feeding the solution into the first cavity and sucking it from the second. In this case, the board under the action of the flow of diluent throttled by the holes of the first cavity cavity, adjoins with its entire plane to the plane of the second volume, which excludes deformation and oscillation of the thin and flexible circuit. Then, the flow direction is changed, creating an overpressure in the second volume, and in the first discharge - under the same pressure. The frequency of the reversal is chosen depending on in s2 up to 60 cycles in the bone of the solution from a minute. The method of processing printed circuit boards makes it easy to automate the entire cycle of chemical processing of boards with a high quality of processing holes of various diameters with different thickness and size of boards, number and diameter of holes. Claims of chemical processing of a printed circuit board, including forcing the working solution into the treatment area of the board with throttling and reversing flow, characterized in that in order to improve the quality of the processing of the boards, the flow of the working solution is throttled over the entire surface of the board. - on one side of the board and underpressure on the other at a solution flow pressure of 0.05– 0.3 kg / cm, and reversing takes place at a frequency of 10–60 cycles per minute. Sources of information taken into account in the examination 1. USSR author's certificate number 41533, cl. From 23 to 3/00, 1971.

2. USSR author's certificate number i 2if33, cl. H 05 K 3/18, 1971 (prototype).