Ultra-precision PCB Fabrication, High Frequency PCB, High Speed PCB, IC Substrate, Multilayer PCB and PCB Assembly.
The most reliable PCB custom service factory.
PCB Tech

PCB Tech

PCB Tech

PCB Tech

PCB circuit board production process
2021-09-24
View:33
Author:Aure

PCB circuit board production process



Flow chart of single panel process production

Cutting-drilling-outer layer graphics (screen printing circuit)-circuit inspection-etching-etching inspection-inspection-screen printing solder mask (ink)-spray tin (hot air leveling)-silk screen characters (Text)——Shape processing (forming gong edge)——Test——FQC——Warehousing——Shipment

Production flow chart of double-sided tin spraying board process

Cutting——Drilling——Immersion Copper Thickening——Outer Layer Graphics (Silk Printing Line)——Plating (Copper Surface Thickening)——Etching——Secondary Drilling——Inspecting EQC——Silk Printing Solder Mask (Ink )-Hot air leveling (spray tin)-silk screen characters (text)-shape processing (forming)-testing-inspection FQC-storage-shipment

Process flow chart of multi-layer tin-sprayed board production


PCB circuit board production process



Cutting-drilling positioning holes-inner layer graphics (inner layer lines)-inner layer etching-inspection-blackening (browning)-lamination (pressing)-drilling-copper sinking Thickness-outer layer graphics (line)-etching-secondary drilling-inspection-silk screen solder mask (ink)-hot air leveling (spray tin)-silk screen characters (text)-shape processing ( Forming)——Test——Inspection FQC——Warehousing——Packing and shipping

1. Cutting

Pay attention to size, material, thickness, copper thickness

Material: fiberglass board, aluminum substrate, copper substrate, ceramic board, cardboard. . . . . .

Thickness: 0.4, 0.6, 0.8, 1.0, 1.2, 1.6, 2.0, 3.0MM. . . . . .

Copper thickness: 1OZ, 2OZ, 3OZ, 4OZ

There are also some special treatments. Customers require additional baking for 2-4 hours to test the temperature resistance and thermal conductivity of the board (generally aluminum substrates are better)

The order of thermal conductivity: ceramic board, copper substrate, aluminum substrate, fiberglass board, cardboard. . . . . .

2. Drilling

Aperture: 0.25, 0.3, 0.35mm... the ones below 0.3mm are more difficult, the knife is easy to break when drilling, there are piercings, burrs, dust, and easy to block holes.

Three, drilling inspection

Each process requires inspection, machinery and equipment, or labor, in order to reduce costs, reduce scrap rate, and shorten delivery time.

The main problems of drilling: empty deviation, burrs, burrs, dust, plugging, leaking holes in the hole, using the wrong tool.

Fourth, sink copper

20-60 minutes customer special requirements,.

Five, heavy copper inspection

Whether the copper surface is scratched, whether the copper thickness meets customer requirements, and the copper thickness is controlled. [Time and potion work together. Time is controlled by humans. The potion needs to be tested by a laboratory technician at least three times a day (hard board) and flexo board at least once every 2 hours. 】

Six, line

The principle of physics transforms an image into a real object. A layer of oil (line oil) is printed on the copper surface. If the line is not very dense, use a wet film (dry area); if the line is dense and difficult to make, use a dry film. Then bake for 15 to 30 minutes, aligning, exposing, exposure machine, there is radiation, it is a large energy lamp, usually a few kilowatts, this graphic is transformed into a real object, developed, and the board can be seen after it comes out.

Seven, line inspection

Check whether the alignment is biased, whether there is an open or short circuit, and whether the current wide line spacing meets customer requirements

8. Secondary electric copper

Through the action of electric ions and chemical methods, the copper is attached to the metal surface to achieve the copper thickness required by the customer. Note the magnitude of the current. If it is big, it will burn the board, if it is small, the adsorption effect will not be achieved. The surface appears dull and rough

9. Start tinning (process, immersion gold, OSP, immersion tin, spray tin)

10 to 20 minutes, mainly to protect the pads from being etched away

10. Etching

After etching the circuit, the finished solder mask is produced. The main components of the etching solution are ammonia and sulfuric acid.

The problem of etching attention is that the etching is excessive, which causes the circuit to be too thin, which does not meet the customer's requirements. The etching is not clean (clean) causing a large area of short circuit between the lines. After etching, there is no room for rework.

Eleven, remove the film and remove the tin

Return the line oil and return the tin. Use the machine to remove the tin on the board through the stripping water.

12. Etching inspection (inspection)

Whether the line width and line spacing of the etching circuit meets the requirements, and whether there is an open or short circuit, and the etching is not clean.

13. Screen printing solder mask

The whole board is covered with oil, and there is an insulating layer. The drying (30 minutes to an hour) depends on the ink (red oil, white oil, blue oil, black oil).

Pay attention to the via hole cover oil, or the via hole plug hole. Be sure to ask the customer clearly.

Alignment, exposure, development and post-out of solder mask. The main ingredient of the developer's potion is NAH3COG.

14. Solder mask inspection

The development is not clean, the exposure is poor, and whether the solder resist pad is offset. Whether the surface of the board is painted or not.

15. Silk screen characters (some customers do not require printing)

The characters are required to be clear and full, no missing characters, wrong printing, reverse printing, overprinting, and no blurring of characters.

16. Process, immersion gold, spray tin, OSP special treatment and blue glue.

17. Forming

Types of molding: CNC gong edge, die punching board.

Pay attention to the size, there is no indentation on the board surface (die punching).

The size needs to be the first piece, and the first inspection and measurement (micrometer, caliper-the measurement is recorded), some customers pay special attention to the strict tolerance of the shape within ±0.1 MM

18. Test

Test types: visual inspection (visual inspection), test stand test, flying probe test

According to customer requirements, the test is mainly to detect open and short circuits, as well as the insulation of the board.

High-volume, open test, 100% good board shipment, small-volume, flying probe test, slow speed, but convenient, low cost. The quality can reach 100%.

19. FQC finished product inspection

Whether the process is wrong, the thickness of the finished product, the pore size, and whether the ink enters the hole. Responsible for cleaning up the number, whether there is enough.

Twenty, random inspection

Proportionally, large batches, 20%-50% sampling. Full inspection in small batches. Attached with shipping report, board report, slicing report, product quality certificate.

ipcb is a high-precision, high-quality PCB manufacturer, such as: isola 370hr pcb, high-frequency pcb, high-speed pcb, ic substrate, ic test board, impedance PCB, HDI PCB, Rigid-Flex PCB, buried blind PCB, advanced PCB, microwave PCB, telfon pcb and other ipcb are good at PCB manufacturing.