Flexible Circuits & Printed Circuit Boards

Today we have a look at the aluminum PCB production process. Please see below details.

First, Cut matetial;

Second, drilling holes

Third, the dry / wet developing
1, Dry / wet film developing process: nogplate – film – exposure – developing

Fourth, the acid / alkaline etching
1, Acid / alkaline etching process:  etching – Stripping – dry – check board

Fifth, silkscreen soldermask and characters.

Sixth, V-CUT outline;

Seventh,  testing, OSP;

Final, FQC, FQA, packaging, shipping.

The aluminum PCB production process is almost the same as other rigid pcb. CMD Cirsuits have a very strict qualtiy control system for the aluminum pcb and flexible pcb products, we pride ourselves on our quality and this is our selling point. Please contact us for any inquiry.

Today let’s have a look at the PCB design and cost controlling, in order to allow the PCB cost the lower the better, there are many design factors must be taken into considerations:

1, The board size. Smaller board, the lower the cost. Part of the PCB size has become the standard, as long as the cost according to standard size as it will naturally decrease.
 
2, The cost of SMT is lower than THT, because the parts on the PCB will be more intensive (also small).

3, If the board is very dense with components , then the trace must be more detailed, we should use the advanced equipments and expensive material. The cost of these questions, much more than the cost of reduce the PCB size.

4, The more layers, the higher the cost, but less PCB layers usually result in an increase in size. The cost of multilayer pcb much more higher than single-sided pcb
 
5, Drilling will take time, so the holes the less the better.

6, Buried holes compare tp through plated holes is expensive. Because the buried holes must be drilled before stitching.

7, The size of the holes on the board in accordance with parts to determine the diameter of the pin. If the board has a different type of pin parts, then because the machine can not use the same drill all the holes drilled, Comparison of the relative time-consuming, so it represents to  increase manufacturing costs.
 
8, Fly test, usually expensive than optical methods. Generally speaking, optical test is sufficient to ensure no errors on the PCB.

To know the PCB manufacturing process is very useful, which allows us to know where we should to control. So we know these can be taken into account when we design PCB, and reducing PCB costs.

Would you like to know the flexible pcb production capabilities and tolerances of CMD circuits? Please see below CMD can make for you.

1. tolerance of overall thickness   +/-0.03mm
2. positional and dimensional tolerance of edges and holes   about +/-0.10mm
3. minimum trace width and spacing (1/2 oz. copper)     0.05mm/0.05mm
4. minimum distance of traces and holes to an edge of the flex pcb 0.15mm, better is 0.20mm

These are the most common tolerances of the flexible pcb, if your board have more strict required, please send us to check if we can make.

CMD Circuits specilize in making flexible pcb, flexible circuits, rigid pcb, aluminum pcb.

Now the popular of the FPC surface plating is ENIG, but what’s the ENIG? It’s Nickel Immersion Gold.

The flexible circuits copper surface is plated of Ni/Au. The deposition thickness of the inner Ni layer is generally3~6um, the deposition thickness of the outer Au thin, usually 0.03 ~ 0.1um. Ni as the barrier layer between Cu and soldering tin. Welding, outside Au in the solder which melts rapidly with soldering tin and then turn into Ni/Sn intermetallic compounds with inner Ni. The gold-plated to prevent Ni oxidation during storage or passive, it should be enough gold plating density, the thickness can not be too thin.

CMD Circuits almost all flexible circuits are with the ENIG plated for customers, all of our staff are with the many years experience in line, and our customers are very satisfy with our quality when they compare with others’.

Relative Posts:
1. The structure of FPC;
2. the whole thickness of FPCs;
3. Flexible Circuits Production Process.

There are normal three kinds of coverlayer of flexible circuits(flexible pcb), please see below thickness:

1)12.5UM:     PI：12.5UM    AD：15UM           Thickness：27.5UM

                         PI：12.5UM    AD：25UM           Thickness ：37.5UM
             
2)  25UM:     PI：25UM     AD：25UM            Thickness：55UM

If you need any other information of flexible circuits and flexible pcb, please contact us anytime.

The structure of double-sided aluminum pcb is generally divided into three layers: first layer of a copper foil; the second layer is the thermal insulation materials; third layer is the aluminum substrate.

The fundtion of these three layers of double-sided aluminum pcb: first layer copper foil is made as circuits(conductive). The second layer is the key to check if it has the ability to play the fast passed the heat generated LED to aluminum substrate, it is necessary to know the resistance of thermal insulation materials. The function of the third layer is the aluminum substrate pass the heat from thermal insulating material to lamps again. It also has a installation function.

Thermal conductivity of aluminum pcb is not only has a relationship with the lamps, the most critical depends on the performances of thermal insulation materials.

This time let’s talk about the PCB Dry film photoresist structure and main components.

1. PCB Dry film photoresist structure:

Dry film photoresist consist of the polyester film, photoresist film and polyethylene protective film three parts.

Polyester film is the based of Photosensitive layer, the thickness is usual 25um.
 
Polyethylene film is a protective film covered with a photosensitive layer on the top to prevent dirt dry dust and dirt.
General thickness of polyethylene film is also 25um.

Photoresist was the subject of dry filmmany,mostly is the negative light material.

2.The main components of photoresist film  :

1) binder (film-forming resin)

2) Light monomer

3) Photoinitiator

4) Plasticizer

5) tackifier

6) thermal polymerization inhibitor

7) pigment

(8)  Solvent
The solvent must be used to dissolve the above components, usually acetone and alcohol.

If you want to know more about produce procedure the rigid pcb,aluminum pcb, please contact with us anytime.

In general, the master film is also known as the black film, mainly used to copy the work film (yellow film), but not necessarily only a yellow film for work, are also black films do work. It mainly to do high-precision HDI board or to a one-time savings in the production of small quantities of circuit boards and flexibe pcb. Yellow films mainly used in ordinary printed circuit boards and mass production.

Positive film for the use of graphical electroplating, developing is the circuits, leaving the role of anti-corrosion plating, mainly tin and pb plating. Negatives film used for direct etching, leaving the role of circuits. When distinguish the films, the smooth side is black film, in contrast, is yellow film. And generally use scratching pen to scratch the film can be seen smooth side.

Please Note: There are both glossy and matte side of yellow film, and the second is easy to find easy-to-oil surface indentation when using. On film circuits (copper), the transmitting is negative film, opaque positive film.

CMD Circuits is specializing in manufacturing the printed circuit boards, flexible pcb and aluminum pcb, please contact us if any inquiries.

Aluminum PCB is one of metal-based pcb,including copper foil,thermal insulating layer and metal substrate three parts,and now the aluminum pcb is widely used in the many applications.

1. Audio devices: input,output amplifiers,balanced amplifiers,audio amplifiers,preamplifiers,power amplifiers and so on.
2. Power Supply: Switching Regulator,DC / AC converter,SW regulator and so on.
3. Telecommunications electronic equipments: high-frequency electric amplifiers,transmitter circuit board.
4. Office automation equipments: motor drive,and so on.
5. Automotive: Electronic Ignition,power controller.
6. Computer: CPU board,power controller,floppy disk drive devices.
7. Power modules: converter,power rectifier bridges.
8, lamp lighting: As an advocate to promote energy-saving lamps and colorful energy-saving LED lights are very popular by the market,while the aluminum pcb used in LED lights have begun a large-scale applications.
CMD Circuits have provided the high quality and competitve cost aluminum pcb,aluminum base pcb and other metal base pcb. Please contact us if you have any inquires.

In the PCB drilling process may have the following quality problems:
1, partial hole, porous & leak holes;
2, broken drill bits;
3, blocking the hole (hole with debris);
4, no drill through;
5, burr hole, rough, smudge;
6, the surface burrs.

Here is a quick solution of pcb  drilling quality problems. The method is from 1 to last to  find out the problems.

1. Check the settings of drilling parameters are correct, mainly speed and lower speed. Confirmed whether it is setting or procedural issue.

2. If drilling parameters are right, put printed circuit boards on two machines(Note: to be the same machine model),and using the same or different settings of drilling to confirm the problem is the machine problems or procedural issues. As the probability is too less of the two machine have the same problems, then you can know the problem is the The equipment or procedural problems.

3. If the problems still have, replace of the raw materials and test materials.

4. If the problem still have, replace of the drill bit to test, generally the brand-name manufacturers drilling bits with less problems.

CMD Circuits have the strict quality control systems to ensure the quality of our producting, including rigid pcb, flexible pcb, aluminum pcb and all items. Please contact with us if you need any further information.