Confident Company for Surface Finish PCB
Only PCBTok will satisfy all your diverse Surface Finish PCB needs.
- Your PCB designs are planned using Altium, Protel, and Eagle
- We choose the appropriate circuit segments for your PCB
- Reduce tarnish and extra expense for your products
- Fast turnaround time, WIP report while you wait
We are here to serve you any way we can.
PCBTok Delivers Trustworthy Surface Finish PCB
Once you’ve placed your PCB order, durability is crucial.
You need surface finishing in your PCB for this.
We refer to these PCBs as Surface Finish PCBs
Thanks to our excellent standards, we can assure you that our product will last you for a very long period.
Our circuit boards have a lower defect rate, as we meet stringent international standards. Inquire now!
Surface Finish PCB and PCB assembly are areas of our areas of expertise. We can provide you all the details you need in this article write-up.
Surface Finish PCB By Type
Surface Finish PCB By Layer (6)
Surface Finish PCB By Feature (6)
Highly Competent with PCB Surface Finish
Our area of expertise is PCB Surface Finish.
What else can PCBTok offer?
We’ve got senior PCB professionals on our engineering team.
Not just China, but also other international PCB manufacturing businesses have trained them.
Without a doubt, our crew are adept at meeting your PCB needs.
Call right away and put your trust in our knowledgeable PCB team!
Good Surface Finish Manufacturing Method
From the starting process to PCB finishing, we are able to produce PCBs for you.
- Free sample for bulk orders, just inquire
- 24/7 IT support and back-up
- Full-fledged company, mature in PCB business
- Handle bulk order and fast-track order quickly
Good Surface Finish manufacturing methods—that’s just what we do.
Contact us right away! We will make a difference in your business.
Safe and Cost-Effective Surface Finish PCB
The uncontested authority on all things PCB is PCBTok.
Our PCBs with Surface Finish that are applied on HDI, High-Frequency, High-Tg, Rogers, and other technologies are all reliable.
Our business is a source of cutting-edge materials—we don’t use imitations!
Any laminate thickness between 0.25 and 2 oz can be specified, depending on the requirements of your device.
Finally, we provide customizable payment plans based on your unique circumstances.
The Surface PCB Without Compromise
As your top-tier PCB, we adhere to standards around the world for PCBs like:
- For Quality Management Systems, see ISO-9001:2015
- Environmental Safety: ISO 14001:2015
- Canadian and American UL Certification
- Other pertinent regulations applicable to your locale
Additionally, we regularly attend Electronica Munich to stay current with Surface Finish PCB trends.
Surface PCB Fabrication
We sell our Surface PCB boards for industrial applications that call for frequent use.
They are offered for sale to domestic as well as our loyal foreign buyers.
We sell these and receive positive, five-star evaluations.
Customers who order them utilize them in wireless and digital PCBs.
This Surface Finish PCB product line benefits backhaul radio, semiconductors, Bluetooth devices, wifi-6 devices, and similar goods.
We source our Surface PCB Quality Materials from reliable, environmentally conscious vendors.
You don’t have to worry about that aspect because we align our company with excellent environmental practices in the PCB trade.
A PCB’s surface polishing requires technical skill. Make sure the people performing it are professionals.
Because of this, you can rely on the staff at PCBTok to create excellent parts for you.
OEM & ODM PCB Surface Finish PCB Applications
The preferred PCB types for medical equipment are Flex and Rigid-Flex. To guarantee that these products are safe before they are used by people, you require a superior Surface Finish PCB.
Surface Finish PCB Production Details As Following Up
|1||Layer Count||1-20 layers||22-40 layer|
|2||Base Material||KB、Shengyi、ShengyiSF305、FR408、FR408HR、IS410、FR406、GETEK、370HR、IT180A、Rogers4350、Rogers400、PTFE Laminates(Rogers series、Taconic series、Arlon series、Nelco series)、Rogers/Taconic/Arlon/Nelco laminate with FR-4 material(including partial Ro4350B hybrid laminating with FR-4)|
|3||PCB Type||Rigid PCB/FPC/Flex-Rigid||Backplane、HDI、High multi-layer blind&buried PCB、Embedded Capacitance、Embedded resistance board 、Heavy copper power PCB、Backdrill.|
|4||Lamination type||Blind&buried via type||Mechanical blind&burried vias with less than 3 times laminating||Mechanical blind&burried vias with less than 2 times laminating|
|HDI PCB||1+n+1,1+1+n+1+1,2+n+2,3+n+3(n buried vias≤0.3mm),Laser blind via can be filling plating||1+n+1,1+1+n+1+1,2+n+2,3+n+3(n buried vias≤0.3mm),Laser blind via can be filling plating|
|5||Finished Board Thickness||0.2-3.2mm||3.4-7mm|
|6||Minimum Core Thickness||0.15mm(6mil)||0.1mm(4mil)|
|7||Copper Thickness||Min. 1/2 OZ, Max. 4 OZ||Min. 1/3 OZ, Max. 10 OZ|
|9||Maximum Board Size||500*600mm(19”*23”)||1100*500mm(43”*19”)|
|10||Hole||Min laser drilling size||4mil||4mil|
|Max laser drilling size||6mil||6mil|
|Max aspect ratio for Hole plate||10:1（hole diameter＞8mil）||20:1|
|Max aspect ratio for laser via filling plating||0.9:1(Depth included copper thickness)||1:1(Depth included copper thickness)|
|Max aspect ratio for mechanical depth-
control drilling board(Blind hole drilling depth/blind hole size)
|0.8:1(drilling tool size≥10mil)||1.3:1(drilling tool size≤8mil),1.15:1(drilling tool size≥10mil)|
|Min. depth of Mechanical depth-control(back drill)||8mil||8mil|
|Min gap between hole wall and
conductor (None blind and buried via PCB)
|Min gap between hole wall conductor (Blind and buried via PCB)||8mil(1 times laminating),10mil(2 times laminating), 12mil(3 times laminating)||7mil(1 time laminating), 8mil(2 times laminating), 9mil(3 times laminating)|
|Min gab between hole wall conductor(Laser blind hole buried via PCB)||7mil（1+N+1）；8mil（1+1+N+1+1 or 2+N+2）||7mil（1+N+1）；8mil（1+1+N+1+1 or 2+N+2）|
|Min space between laser holes and conductor||6mil||5mil|
|Min space between hole walls in different net||10mil||10mil|
|Min space between hole walls in the same net||6mil(thru-hole& laser hole PCB),10mil(Mechanical blind&buried PCB)||6mil(thru-hole& laser hole PCB),10mil(Mechanical blind&buried PCB)|
|Min space bwteen NPTH hole walls||8mil||8mil|
|Hole location tolerance||±2mil||±2mil|
|Pressfit holes tolerance||±2mil||±2mil|
|Countersink depth tolerance||±6mil||±6mil|
|Countersink hole size tolerance||±6mil||±6mil|
|11||Pad(ring)||Min Pad size for laser drillings||10mil(for 4mil laser via),11mil(for 5mil laser via)||10mil(for 4mil laser via),11mil(for 5mil laser via)|
|Min Pad size for mechanical drillings||16mil(8mil drillings)||16mil(8mil drillings)|
|Min BGA pad size||HASL:10mil, LF HASL:12mil, other surface technics are 10mil(7mil is ok for flash gold)||HASL:10mil, LF HASL:12mil, other surface technics are 7mi|
|Pad size tolerance(BGA)||±1.5mil(pad size≤10mil);±15%(pad size>10mil)||±1.2mil(pad size≤12mil);±10%(pad size≥12mil)|
|1OZ: 3/4mil||1OZ: 3/4mil|
|2OZ: 4/5.5mil||2OZ: 4/5mil|
|3OZ: 5/8mil||3OZ: 5/8mil|
|4OZ: 6/11mil||4OZ: 6/11mil|
|5OZ: 7/14mil||5OZ: 7/13.5mil|
|6OZ: 8/16mil||6OZ: 8/15mil|
|7OZ: 9/19mil||7OZ: 9/18mil|
|8OZ: 10/22mil||8OZ: 10/21mil|
|9OZ: 11/25mil||9OZ: 11/24mil|
|10OZ: 12/28mil||10OZ: 12/27mil|
|1OZ: 4.8/5mil||1OZ: 4.5/5mil|
|1.43OZ（negative ）:5/8||1.43OZ（negative ）:5/7|
|2OZ: 6/8mil||2OZ: 6/7mil|
|3OZ: 6/12mil||3OZ: 6/10mil|
|4OZ: 7.5/15mil||4OZ: 7.5/13mil|
|5OZ: 9/18mil||5OZ: 9/16mil|
|6OZ: 10/21mil||6OZ: 10/19mil|
|7OZ: 11/25mil||7OZ: 11/22mil|
|8OZ: 12/29mil||8OZ: 12/26mil|
|9OZ: 13/33mil||9OZ: 13/30mil|
|10OZ: 14/38mil||10OZ: 14/35mil|
|13||Dimension Tolerance||Hole Position||0.08 ( 3 mils)|
|Conductor Width(W)||20% Deviation of Master
|1mil Deviation of Master
|Outline Dimension||0.15 mm ( 6 mils)||0.10 mm ( 4 mils)|
|Conductors & Outline
( C – O )
|0.15 mm ( 6 mils)||0.13 mm ( 5 mils)|
|Warp and Twist||0.75%||0.50%|
|14||Solder Mask||Max drilling tool size for via filled with Soldermask (single side)||35.4mil||35.4mil|
|Soldermask color||Green, Black, Blue, Red, White, Yellow,Purple matte/glossy|
|Silkscreen color||White, Black,Blue,Yellow|
|Max hole size for via filled with Blue glue aluminium||197mil||197mil|
|Finish hole size for via filled with resin||4-25.4mil||4-25.4mil|
|Max aspect ratio for via filled with resin board||8:1||12:1|
|Min width of soldermask bridge||Base copper≤0.5 oz、Immersion Tin： 7.5mil(Black), 5.5mil(Other color) , 8mil( on copper area)|
|Base copper≤0.5 oz、Finish treatment not Immersion Tin ： 5.5 mil(Black,extremity 5mil), 4mil(Other
color,extremity 3.5mil) , 8mil( on copper area
|Base coppe 1 oz: 4mil(Green), 5mil(Other color) , 5.5mil(Black,extremity 5mil),8mil( on copper area)|
|Base copper 1.43 oz: 4mil(Green), 5.5mil(Other color) , 6mil(Black), 8mil( on copper area)|
|Base copper 2 oz-4 oz: 6mil, 8mil( on copper area)|
|15||Surface Treatment||Lead free||Flash gold(electroplated gold)、ENIG、Hard gold、Flash gold、HASL Lead free、OSP、ENEPIG、Soft gold、Immersion silver、Immersion Tin、ENIG+OSP,ENIG+Gold finger,Flash gold(electroplated gold)+Gold finger,Immersion silver+Gold finger,Immersion Tin+Gold finge|
|Aspect ratio||10:1(HASL Lead free、HASL Lead、ENIG、Immersion Tin、Immersion silver、ENEPIG);8:1(OSP)|
|Max finished size||HASL Lead 22″*39″；HASL Lead free 22″*24″；Flash gold 24″*24″；Hard gold 24″*28″；ENIG 21″*27″；Flash gold(electroplated gold) 21″*48″；Immersion Tin 16″*21″；Immersion silver 16″*18″；OSP 24″*40″；|
|Min finished size||HASL Lead 5″*6″；HASL Lead free 10″*10″；Flash gold 12″*16″；Hard gold 3″*3″；Flash gold(electroplated gold) 8″*10″；Immersion Tin 2″*4″；Immersion silver 2″*4″；OSP 2″*2″；|
|PCB thickness||HASL Lead 0.6-4.0mm；HASL Lead free 0.6-4.0mm；Flash gold 1.0-3.2mm；Hard gold 0.1-5.0mm；ENIG 0.2-7.0mm；Flash gold(electroplated gold) 0.15-5.0mm；Immersion Tin 0.4-5.0mm；Immersion silver 0.4-5.0mm；OSP 0.2-6.0mm|
|Max high to gold finger||1.5inch|
|Min space between gold fingers||6mil|
|Min block space to gold fingers||7.5mil|
|16||V-Cutting||Panel Size||500mm X 622 mm ( max. )||500mm X 800 mm ( max. )|
|Board Thickness||0.50 mm (20mil) min.||0.30 mm (12mil) min.|
|Remain Thickness||1/3 board thickness||0.40 +/-0.10mm( 16+/-4 mil )|
|Tolerance||±0.13 mm(5mil)||±0.1 mm(4mil)|
|Groove Width||0.50 mm (20mil) max.||0.38 mm (15mil) max.|
|Groove to Groove||20 mm (787mil) min.||10 mm (394mil) min.|
|Groove to Trace||0.45 mm(18mil) min.||0.38 mm(15mil) min.|
|17||Slot||Slot size tol.L≥2W||PTH Slot: L：+/-0.13(5mil) W：+/-0.08(3mil)||PTH Slot: L：+/-0.10(4mil) W：+/-0.05(2mil)|
|NPTH slot(mm) L+/-0.10 (4mil) W：+/-0.05(2mil)||NPTH slot(mm) L：+/-0.08 (3mil) W：+/-0.05(2mil)|
|18||Min Spacing from hole edge to hole edge||0.30-1.60 (Hole Diameter)||0.15mm(6mil)||0.10mm(4mil)|
|1.61-6.50 (Hole Diameter)||0.15mm(6mil)||0.13mm(5mil)|
|19||Min spacing between hole edge to circuitry pattern||PTH hole: 0.20mm(8mil)||PTH hole: 0.13mm(5mil)|
|NPTH hole: 0.18mm(7mil)||NPTH hole: 0.10mm(4mil)|
|20||Image transfer Registration tol||Circuit pattern vs.index hole||0.10(4mil)||0.08(3mil)|
|Circuit pattern vs.2nd drill hole||0.15(6mil)||0.10(4mil)|
|21||Registration tolerance of front/back image||0.075mm(3mil)||0.05mm(2mil)|
|22||Multilayers||Layer-layer misregistration||4layers:||0.15mm(6mil)max.||4layers:||0.10mm(4mil) max.|
|Min. Spacing from Hole Edge to Innerlayer Pattern||0.225mm(9mil)||0.15mm(6mil)|
|Min.Spacing from Outline to Innerlayer Pattern||0.38mm(15mil)||0.225mm(9mil)|
|Min. board thickness||4layers:0.30mm(12mil)||4layers:0.20mm(8mil)|
|Board thickness tolerance||4layers:+/-0.13mm(5mil)||4layers:+/-0.10mm(4mil)|
|8-12 layers:+/-0.20mm (8mil)||8-12 layers:+/-0.15mm (6mil)|
|26||Impedance control||±5ohm(＜50ohm), ±10%(≥50ohm)|
PCBTok offers flexible shipping methods for our customers, you may choose from one of the methods below.
DHL offers international express services in over 220 countries.
DHL partners with PCBTok and offers very competitive rates to customers of PCBTok.
It normally takes 3-7 business days for the package to be delivered around the world.
UPS gets the facts and figures about the world’s largest package delivery company and one of the leading global providers of specialized transportation and logistics services.
It normally takes 3-7 business days to deliver a package to most of the addresses in the world.
TNT has 56,000 employees in 61 countries.
It takes 4-9 business days to deliver the packages to the hands
of our customers.
FedEx offers delivery solutions for customers around the world.
It takes 4-7 business days to deliver the packages to the hands
of our customers.
5. Air, Sea/Air, and Sea
If your order is of large volume with PCBTok, you can also choose
to ship via air, sea/air combined, and sea when necessary.
Please contact your sales representative for shipping solutions.
Note: if you need others, please contact your sales representative for shipping solutions.
You can use the following payment methods:
Telegraphic Transfer(TT): A telegraphic transfer (TT) is an electronic method of transferring funds utilized primarily for overseas wire transactions. It’s very convenient to transfer.
Bank/Wire transfer: To pay by wire transfer using your bank account, you need to visit your nearest bank branch with the wire transfer information. Your payment will be completed 3-5 business days after you have finished the money transfer.
Paypal: Pay easily, fast and secure with PayPal. many other credit and debit cards via PayPal.
Credit Card: You can pay with a credit card: Visa, Visa Electron, MasterCard, Maestro.
“I like this Chinese business named PCBTok. They did a terrific job of outlining everything and taking care of the project’s additional assistance right away. They finished the task much earlier than expected. They are consistently professional, and I heartily endorse them to anyone looking for work of the highest caliber. Once again, thank you for making my life less of a pain”.Damon Dixon, Commodity Manager from North Carolina, USA
“I’m happy to have met this PCBTok. My PCB order received wonderful results and excellent customer service; my first one was the bomb! I loved how they sent you emails to let you know how your project was doing. If I had any more needs, I’d without a doubt go back there. They carried out the exact request I made of them. They are really honest and perform excellent work.”Darcee Hastings, CAD/PCB Librarian & Layout Engineer from Scotland, UK
“We had a fantastic day at this PCB shop. Salesman did an excellent job and assisted us very quickly. He was quite pleasant before stating that it was only his job to be the best on the job. The very best service I’ve ever experienced. Thank you, PCBTok team! This company and you are the best! With PCBTok, I have the feeling that it was a trustworthy buddy looking out for me.”Oleg Soldatov, Purchasing Director from Lithuania
PCB Surface Finish – The Completed FAQ Guide
The surface finish of the PCB is an important factor to consider during the design process. A good finish protects the copper layer from oxidation and improves solderability on the PCB. However, surface finish is more than just appearance. Continue reading to learn more about its significance. We’ll look at some common concerns and answer some of your questions in this article. We’ll also discuss the benefits and drawbacks of various surface finishes.
There are a number of things to consider before deciding on the type of finish for your PCB. Whether your PCB is a high-end product for a lifetime of use or an inexpensive hobbyist project for only occasional use, the surface finish of the PCB is critical. Each option has pros and cons, and you should make your final choice after considering the performance, price, and in-line testing requirements of your electronics.
Surface finish is an important aspect of PCB production and has a significant impact on the quality of the final product. It can help prevent copper layer oxidation, which can reduce solderability. Using a PCB surface finish prevents copper oxidation, which can affect the reliability of the finished product. In addition, a good surface finish ensures that solder quality is maintained and that the electrical properties of the board remain excellent.
What Is PCB Surface Finish
There are several available PCB finishes, each with advantages and disadvantages. Some are organic and some are lead-free. An immersion tin is the best choice for a lead-free finish. The chemical process produces a flat surface for fine asphalt components. It is also environmentally friendly because it uses fewer chemicals and water. You should also look for PCBs that comply with RoHS regulations.
The surface finish of a circuit board is an important factor to consider when designing electronic products. To determine which type of finish is best for your product, consider its usage and operating time. The following table summarizes the various types of PCB finishes and their associated costs. Each type has advantages and disadvantages. Read on for more information. These are the primers for the various types of PCB finishes.
The PCB finish is used to protect the PCB’s exposed copper circuitry. This is important because it prevents copper from oxidizing, which can reduce the solderability of the final product. Various finishes prevent copper oxidation, resulting in superior electrical performance and solderability. However, the process of applying these finishes can be complex and error-prone. It is critical to understand the role of each surface finish.
OSP, on the other hand, is an organic water-based surface treatment that forms a thin protective layer on the copper surface of PCBs. This layer provides an organometallic layer over the copper and protects the circuit from oxidation. OSP is very environmentally friendly because it is an organic surface treatment, whereas other PCB surface treatments require a lot of energy and toxic chemicals.
The most common type of PCB surface treatment is lead-free HASL, which is also the most affordable. HASL, on the other hand, leaves a rough surface and is not recommended for fine pitch assemblies. Lead-free solder spraying is not a good choice for high-reliability products, and other lead-free alternatives may be preferable. HASL has some advantages.
Immersion Gold Surface Finish
Immersion silver is another popular PCB finish and is an excellent choice for customers who need a flat surface and are on a tight budget. The immersion process is inexpensive and requires very little water and chemicals. It is also useful in applications where copper surface roughness is critical. However, it is not always the best choice for every application, and some PCB manufacturers do not offer it.
Another type of surface finish is carbon ink. This PCB finish is commonly used for RF shielding, keypads, remote controls, and automotive parts. Carbon ink can be printed on almost any type of board, but it requires precise print control. Carbon ink PCBs are also ideal for soldering machines and keyboards. Carbon ink PCBs are expensive to manufacture, but they have a long shelf life and excellent metal-to-metal bonding.
The most common finishes are HASL and ENIG, both of which are RoHS compliant and offer advantages. When not soldered, the gold layer provides excellent electrical conductivity, while the nickel layer protects the gold. Despite their similarities, ENIG is relatively thin and inexpensive. It does, however, have some disadvantages. HASL is not aerospace certified and can be problematic if the gold layer is separated from the nickel layer by a phosphorus layer.
Another common PCB surface finish is HASL. In this process, the board is dipped into a molten alloy, which is then removed with an air knife. Because the copper layers on the PCB remain protected, delamination is less likely. The HASL process can detect delamination problems before expensive components are attached. It is also the most cost-effective type of PCB surface preparation.
Surface finish is an important consideration when designing circuit boards. While HASL is the industry standard for high durability solder joints, ENIG is a more environmentally friendly alternative. ENIG is the preferred solution in many applications, but HASL is also suitable for certain applications, such as low-cost, high-durability solder joints. Both ENIG and HASL are effective in preventing board corrosion, but the environmental benefits outweigh the low cost and high strength of HASL.
LF HASL Surface Finish
HASL is often preferred by manual soldering professionals due to its ease of use in manual soldering. Due to the surface finish, solder alloys adhere easily and form strong joints. The copper layer prevents oxidation because the PCB is coated with a thin layer of sunken gold. Therefore, HASL is a popular choice for high-reliability applications. However, it is not always the best choice.
High-reliability, high-performance electronics use HASL PCB surface treatment. Another advantage of this PCB surface treatment is its organic nature. Water-based finishes are also popular because they provide a flat surface for connecting PCB components. They are also very inexpensive. So, which one should you choose?
As a low-cost alternative to submerged gold, HASL PCB finishes can be applied to all copper surfaces on the board. However, the application process is complex and some PCB manufacturers outsource it. HASL has improved over time, but it still has similar drawbacks to immerion gold, such as uneven surfaces and a hazy appearance.
“What is immersion gold plating?” You may want to know. You are not alone. The process is similar to chemical plating, but there are some key differences. In this process, the gold is not gold-plated metal but is deposited on the copper surface. As a result, the process does not adhere as well as chemical plating. It also has a limited thickness and it does not adhere to the substrate.
Immersion gold plating has many advantages. It is a very reliable method for plating gold PCBs. The most significant advantage of submerged gold plating is its resistance to oxidation. The gold surface is not visible when assembled into a black pad and lasts longer. In addition, PCBTok offers a variety of surface finishes including sputtering, mirror, and brushed finishes.
ENIG Surface Finish
The concentration of copper dissolved in the plating solution determines the amount of gold deposited. It is important to remember that the copper concentration in the plating solution must be high enough to achieve the desired gold deposition. Otherwise, the gold may adhere to the copper surface. Only a few milligrams of gold can be deposited.
The crystal structure of gold plating and gold deposition is another difference. Gold plating has a longer service life compared to submerged gold. In addition, it is more malleable and can be soldered and used in a variety of applications. Due to its higher density and greater flexibility, it can also be used in circuit board production. For PCBs, submerged gold is a popular choice.
You may be wondering what immersion tin plating is. It is a type of plating where the metal is coated with a thin layer of tin. Dip tin is a metal that is used to protect electronic devices from corrosion. It is so thin that if a soldering error occurs, it can be reworked. Tin dip consists of 66 degrees Boehmer sulfuric acid, which is 96% sulfuric acid. This coating is very thin and often soldered immediately, but if the proper conditions are not met, the tin will eventually turn black.
The fact that tin-immersion PCBs have a flat, planar surface is one of their advantages. This makes them ideal for BGA and fine pitch component placement. In addition, dip-tin PCBs are acceptable, which is a significant benefit to electronics manufacturers. However, dip-tinned PCBs may not be suitable for all component types, such as through-hole parts. On the other hand, immersion tinned PCBs are typically thinner and can be assembled without any pressing requirements, thus reducing costs.
Immersion Tin Surface Finish
While the composition of immersion tin plating varies, most are copper-based. The immersion tin composition typically contains a tin salt, acid and reducing agent. The composition is then mixed with copper and the object is immersed in the solution. This method of plating creates a thin layer of tin on the copper. It is important to note that the substrate must be completely clean before immersion tin plating is performed.
There are many factors to consider when choosing a PCB surface finish. Some are cost-related, while others are driven by specific needs or technology. For example, lead-free HASL may be chosen for cost-effectiveness, but may not provide the same co-planarity as other processes. PCB surface treatment protects the surface of the PCB while still allowing it to function properly.
PCB surface treatments include immersion tin and immersion silver. Immersion tin is a thin layer of tin applied to the copper surface of a printed circuit board. These two options are ideal for small geometries, but immersion tin can oxidize, making it unsuitable for long-term shelf life.
Immersion Silver Surface Finish
In some cases, PCB finishes are used to improve the solderability of the board. For example, lead-free solder complies with hazardous material restrictions. This PCB surface finish is suitable for lead bonding but is not compatible with gold. If you are unsure which surface finish to use, please contact PCBTok.
Its purpose is to protect the exposed copper circuitry and ensure solderability. Therefore, PCB surface finish is critical to the performance of high-performance applications. It also prevents copper oxidation. It reduces the possibility of soldering problems.
HASL is a cheaper soldering method than ENIG. ENIG is a lead-free coating that consists of a nickel layer protected by a gold layer. It is also more expensive than HASL, but it offers better electrical properties and longer shelf life. This article discusses the advantages and disadvantages of these two materials.
HASL is more environmentally friendly than ENIG. The difference between the two coatings is the surface treatment process. HASL uses a corrosive flux to prepare the surface, while ENIG is lead-free. Both finishes must be cleaned before entering the field environment as residues can accumulate in the corrosive cells. Even after rinsing with RO water, the gold finish is easier to clean and has very little residue.
The main advantage of HASL is its ease of use and low cost. Hot air solder leveling is an environmentally friendly solution. The disadvantage of HASL is that it is not suitable for mass production. However, it is still much less expensive for small numbers of boards. It also has a better surface finish than HASL and is safer. The decision between ENIG and HASL is yours.
The main difference between the HASL and ENIG finishes is the application process. The ENIG finish is not as flat as other finishes and may not be suitable for small pads. However, it has good solderability and long shelf life. HASL is the best choice when you need to finish a product with an extremely flat surface. However, it is more complex and has a higher risk of defects.
ENIG finishes have disadvantages, including high heat exposure. Hot air welding is not suitable for ENIG and can cause plated through-holes to break. Another difference between ENIG and HASL is that ENIG has higher corrosion resistance. It is also more expensive, but it has the added benefit of being more durable. So, what is the difference between ENIG and HASL?
HAL coating has the best solderability. It is strong enough to withstand multiple assembly and storage steps. However, the process requires the PCB to be immersed in liquid solder. As a result, it has an increased thermal load, making it incompatible with thick boards or small through-holes. The difference between HASL and ENIG finishes does not apply to all applications.
Immersion Gold Structure
ENIG is a good material for some PCB applications, but it has some drawbacks. ENIG is more expensive than HAL and has higher yields. However, it is not the best choice for all applications. Solder resist layers can lead to black pads. When gold corrodes nickel, copper loses its ability to conduct signals. The difference between ENIG and HASL is most obvious in applications where long-term stability is required.
Organic Solvent Plasma (OSP) surface treatment is a PCB surface treatment. It is a low-cost option with excellent flatness and ease of application. A conveyorized chemical process or vertical dip tank is used in the process. Several steps are involved, including rinsing. Enhanced morphology is required to improve the bond between the OSP and the board, and micro stretching is required to achieve the proper film thickness.
OSP is becoming increasingly popular because it is low-cost, environmentally friendly, and easy to implement. It is also resistant to thermal cycling. OSP circuit boards are often handled in an environmentally responsible manner. However, some PCBs may be scratched or damaged during the soldering process. This is why OSP boards must be handled and stored with care.
OSP Surface Finish
When choosing a PCB surface finish, keep the final quality of the board in mind. While PCB reliability often requires a PCB surface finish, the final surface finish must also be appropriate for the type of PCB, application, and environment. The table below compares the prices of various surface finishes. For example, OSP PCBs with ball grid arrays, close pitch assemblies, or contact points should use lead-free solder.
OSP PCB finishes are critical to the reliability and shelf life of the PCBA. While OSP PCBs are available in a variety of finishes, it is critical to choose the right finish for the job. A well-polished PCB with a high-quality finish ensures good metal-to-metal bonding, a long shelf life, and a low risk of product failure.
Besides the bare board material, what is the best surface finish for your PCB? is just as important as choosing the right bare board material. The surface finish of your product can have a significant impact on its performance and reliability. When choosing the right surface finish for your PCB, keep the following factors in mind.
Production volume – The type of finish that works best will depend on the number of PCBs you intend to manufacture. Immersion tin finishes can lose their luster quickly, but silver finishes can resist the loss of luster and keep your PCBs looking good for a long time. If your production volume is low, an immersion silver finish is likely the best choice.
Cost – ENIG is cheaper than HASL, but the difference is not significant. HASL is cheaper, but may not meet the same quality standards. The cost of surface finish is also determined by the cost of board manufacturing. PCBs for consumer electronics are usually cheaper, but they can be finished with more expensive finishes if desired. When corrosion is your primary concern, ENIG is the best choice.
Environmental concerns – HASL is not RoHS compliant and has fine pitch component limitations. In addition, HASL produces an uneven surface, making it unsuitable for use in high-reliability products. In addition, it is not lead-free unless specifically requested. Therefore, lead-free coatings can be used for high-reliability products. So, what is the best surface finish for my PCB?
Performance – PCB surface finish is also important in electrical connections. Since copper is the main conductor material on PCBs, it is prone to oxidation. Oxidation of copper has an impact on high-temperature soldering, so a smooth surface protects the copper from oxidation. It also serves as the basis for the connection between the PCB and the component. HASL is a good choice for cost-conscious companies, but not the best choice if your PCB is less coplanar.
For PCB surface preparation, Organic Solderability Preservative (OSP) is a good choice. OSPs naturally bond with copper to form an organometallic layer that protects it from oxidation. Hard gold applications are one of the most expensive PCB finishes, but they offer excellent durability and long shelf life. Some customers prefer hard gold applications, which require bus plating and additional labor.
Immersion Silver: ENIG surface finish is applied prior to the application of the solder resist layer. This finish provides excellent solderability and surface flatness. The underlying copper is an excellent material for solder joints. ImAg is susceptible to sulfur dioxide, which can cause the surface to lose its luster and form an AgS2 layer. Therefore, for applications where solderability is critical, Immersion Silver is a good choice, but ENIG surface finish is more suitable for high-speed PCBs.
Immersion Tin: The least expensive Immersion tin finish, tin protects the underlying copper from oxidation and provides excellent surface flatness for fine pitch assemblies. In addition, dip tin is RoHS compliant, making it an excellent choice for PCBs with fine pitches and small geometries. It is also better for the environment than dip tin because it uses less water and chemicals.