Method for laser-assisted manufacturing of precise circuit

Abstract

The invention discloses a laser-assisted precise circuit manufacturing method, which comprises the following steps that a production board is provided, and circuits needing to be manufactured on the production board comprise a thick circuit with the circuit distance larger than 50 microns and a precise circuit with the circuit distance smaller than or equal to 50 microns; a film is pasted on the production board, exposure treatment is carried out, exposure of the coarse lines and the precise lines is completed, and all gap parts between the precise lines are exposed; developing and etching the production board, wherein the etching amount during etching is controlled to be greater than half of the copper thickness of the circuit, and the bottom layer base material is not exposed; ablating a gap part between the precision circuits by adopting laser to remove a film and a part of copper layer at the gap of the precision circuits; and carrying out etching treatment and film stripping on the production board again, and forming a thick circuit and a precise circuit on the production board. According to the method, the technological process is optimized, the laser ablation and chemical etching combined copper removal mode is adopted in sequence, manufacturing of the precise circuit with the distance smaller than or equal to 50 micrometers can be achieved, the material and machining cost is low, and the technological process is simple.

Description

technical field [0001] The invention relates to the technical field of printed circuit board production, in particular to a method for laser-assisted production of precision circuits. Background technique [0002] The 21st century has entered a highly information-based society, and the demand for information consumption is becoming more and more vigorous. High-speed, high-performance, and thinner and smaller are the mainstream development trends of future electronic products. Microelectronic packaging technology is also developing at a high speed, making it lighter and lighter. There are more and more applications of devices with thinner and higher packaging density, which prompts the circuit board as a supporting platform for electronic components to change to the direction of high density, high integration and miniaturization; therefore, the wiring density of circuit boards is becoming more and more precise. The line width and spacing are gradually developing in the direct...

AI Technical Summary

Problems solved by technology

[0004] The wiring technology of traditional electronic circuits is mainly based on the subtractive method and semi-additive method, while both SAP (semi-additive method) and m-SAP (improved SAP method) need to use chemical copper, flash etching, electroplating, micro-etching, etc. Wet technology, the use of chemical etching method will inevitably have the problem of side erosion, the size of the side erosion is closely related to the thickness of the copper, and the thickness of the bottom copper is less than 12μm, and it will be difficult to manufacture and press the copper foil; and to increase The bonding force between the copper foil and the base material adopts the method of roughening the surface of the copper foil and the surface of the resin, which will increase the processing cost, and the roughened surface will have a bad influence on the transmission of the signal; the above process steps also have complex procedures, High energy consumption, high cost and serious environmental pollution

[0005] In the manufacturing process of circuit boards, precision circuits refer to circuits with a spacing of less than or equal to 50 microns, because there will be side erosion problems in the etching method, and in the case of relatively large copper thickness requirements, it is difficult to manufacture precision circuits only by etching

[0006] Using the subtractive method, thin resist film, vacuum etching, two-fluid etching and other methods can increase the etching factor to more than 2. The copper thickness limit of 50 microns can only achieve a spacing of 75 microns, and it is difficult to make finer lines. Some use the semi-additive method or improved semi-additive method to make fine lines, but increase the process flow of graphic electroplating and copper reduction, which is difficult to control, has many quality problems, and high cost