PCB processing
- Front-end photoplots
This is the first process where we look at your board data, ready for plotting the filmwork. Formats we accept include:-
•Extended Gerber (preferred)
•Standard Gerber
•Gerber X2
•ODB++
•Eagle
•Easy PC
•Proteus
•Protel
Non-preferred formats may incur additional charges, depending on the work involved in converting.
- Material cutting
For multilayer jobs, the inners are cut, imaged, etched, inspected, oxided, and bonded together to form a multilayer panel ready for processing. For single sided or double sided jobs, the material is cut from large sheets. The material types we offer include:-
•FR4 (standard)
•High Tg FR4
•Aluminium
•CEM-1
Please note, the copper weight you request is the finished weight we supply, and for plated boards we start with less copper and plate on top. Other non-standard materials may be possible, please enquire.
- NC Drill
High speed CNC drills enable holes down to 0.2mm to be accurately drilled, larger sizes have no upper limit. Plated slots are also processed at this stage
- Desmear & Graphole
This process provides a base for electrolytically plating holes and slots, and is much quicker than the old fashioned way of electroless plating. The maximum hole to thickness ratio for plating is 8:1, so for example the thickest board we can safely plate with 0.2mm holes is 0.2 x 8 = 1.6mm
- Dry-film image
Boards are laminated with dry-film resist, where artworks are used to expose the tracks and pads of the circuit. After developing off the unwanted dry-film, the boards are ready for plating.
- Electrolytic plating
During this process we plate about 25-30 microns of copper (just under 1oz) on top of the base copper that was used to start the job. This also deposits down the holes, providing a plated connection through all layers (including inners for multilayers). Tin is also plated on top of the copper.
- Etching
All exposed copper on the boards is etched off, leaving the tracks and pads protected by a layer of tin, which is later stripped off.
- Solder mask
A variety of mask colours are available, all photoimageable for accuracy. Colours include:-
•Green (standard)
•Matt Green
•Black
•Matt Black
•Red
•Yellow
•Blue
•Matt Blue
•White
The non-standard colours will cost slightly more, and take longer to process, since a new screen needs to be used to apply the ink. Green is therefore recommended for quick turnaround prototypes.
- Ident legend
A variety of ident colours are available, in both photoimageable (for accuracy) and UV (for speed). Colours include:-
•White (standard)
•Yellow
•Red
•Black
The non-standard colours will cost slightly more, and take longer to process, since a new screen needs to be used to apply the ink. White is therefore recommended for quick turnaround prototypes.
- Surface finish
Surfaces finishes include:-
•Lead-free HASL (standard)
•Leaded HASL (not RoHS)
•ENIG (immersion Gold)
•Immersion Silver
•OSP
•Immersion Tin
For hard gold (edge-connectors, etc) please enquire for availibility and price. Peelable masks and carbon ink is also applied if requested at this stage.
- NC Profile
Shapes ranging from simple squares to complex scored modules with cutouts and slots are available, providing quick and easy breakout after the boards have been assembled by a customer.
- BBT Test
All boards are electrically tested against the supplied data, ensuring any faults are caught (such as artwork breaks).
- Final inspection
The last process before packing is a final inspection, where all boards are visually checked for faults and discarded if found (IPC class 2 criteria).
- Packing
Boards are normally packed into suitable bundles (say 20 per bundle) and vacuum packed for protection, before securely boxing or bagging.
- Despatch
The finished job is sent on whatever courier service specified (normally next day delivery).
Position the mouse pointer over a process for a brief explaination.