| Circuit Board Fabrication And Drilling
Process: |
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| There are two reasons for through-hole drilling
printed circuit boards: |
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Create an opening through the board that will permit a subsequent process to
form an electrical connection between top, bottom, and internal conductor
pathways.
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To permit the board component mounting through with structural integrity and
precision of location.
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The quality of a hole drilled through a printed circuit board is measured by
its ability to interface with the following fabrication processes: plating, soldering, and
forming a highly reliable, non-degrading electrical and mechanical connection.
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Specifications |
Details |
| Material Type |
FR-4, FR-6, FR-8, CEM-1, CEM-3, Aluminium Clad
(Thermagon), Flex, Keratherm, Arlon*, Duroid*, Rogers*, Polyimide*,
Kapton |
| Material Thickness ( in inches) |
0.062”, 0.080”, 0.093”, 0.125”, 0.220”, 0.047”, 0.031”, 0.020”,
0.005" |
| Layer count |
1 to 22 Layers |
| Max. Board Size |
18.00” x 24.00” |
| Drill Clearance |
0.012” |
| Plated Slots |
0.036 or Greater |
| Smallest Hole (Finished) |
0.010 or Greater |
| CNC Route Point |
Any |
| Minimum Route Width |
0.031” |
| Scoring |
Straight Lines, Jump Scoring, Panel Edge to Edge,
CNC* |
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| Imaging: |
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| The process that patterns the metal conductor
to form the circuit. This PCB fabrication process involves a multistep integration of imaging
materials, imaging equipment, and processing conditions with the metallization
process to reduce the master pattern on a substrate. |
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Specifications |
Details |
| IPC Class |
Class II, Class III ,
Class 1 |
| Annular Ring |
5 mil/side or Greater (Min. Design) |
| File Format |
Image : GERBER, 274-D or XDXF, HPGL |
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| ElectroPlating: |
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| Electroplating is the coating of an
electrically conductive object with a layer of metal using electrical current.
The result is a thin, smooth, even coat of metal on the object. A new genre of
high-density interconnect (HDI) boards is making the transition from leading
edge to mainstream. These printed circuit boards are characterized by combining a series of
complexity features that include buried and blind vias, high-aspect ratio
plating, small-hole plating, and fine lines and spaces side by side with ground
plane areas of different sizes. |
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Specifications |
Details |
| Finish Plating |
Solder(HASL), Lead Free Solder(HASL), ENIG (ELectroless
Nickel Immersion Gold), OSP, Immersion Silver, White Tin, Immersion Tin,
Immersion Nickel, Hard Gold, Other |
| Copper Weight |
Outer : Up to 10 oz, Inner : up to 6 oz |
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Trace/Space Width |
5/5 mils or Greater |
| SMD Pitch |
0.080” - 0.020” - 0.010” |
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| Etching Process |
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| Etching Process is one of the major steps in
the chemical processing of subtractive printed boards. It is the removal of
copper, to achieve the desired circuit patterns. Etching is also used for
surface preparation with minimal metal removal (microetching) during innerlayer
oxide coating and electroless or electrolytic planting. Technical, economic,
and environmental needs for practical process control have brought about major
improvements in etching techniques. Batchtype operations, with their variable
etching rates and long downtimes, have been replaced completely with
continuous, constant-etch-rate processes. |
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Specifications |
Details |
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Trace/Space Width |
5/5 mils or Greater |
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| Solder Resist Application: |
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Permanent solder resists may be applied to the PWB by any of several techniques
or pieces of equipment. Screen printing of liquid solder resists is the most
common and the liquid-photoprint solder resists are applied by curtain coating,
roll coating, or blank-screen-printing techniques.
Liquid Photoprint: For some liquid-photoprint solder resists, a screen-printing
technique is used to apply the resist in a controlled manner to the surface of
the PWB. The screen has no image and serves only to control the thickness and
waste of the liquid solder resist. There is no registration of the screen,
since there is no image. The actual solder resist image will be obtained by
exposing the coated PWB with ultraviolet light energy and the appropriate
phototool image. The unexposed solder resist areas defined by the phototool are
washed away during the development step of the PCB fabrication process.
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Specifications |
Details |
| SMD Pitch |
0.080” - 0.020” - 0.010” |
| Soldermask Type |
LPI Glossy, LPI-Matte, SN1000
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| Soldermask Color |
Green, Red, Blue, Black, White, Yellow, Clear |
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| Surface Finishes: |
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| Surface Finish is about
connectivity. It is at the surface where a connection from the board to a
device occurs. Initially soldering and insertion were the preferred methods for
connecting components to the printed board and the circuit board to the system. The dominant
method of assembly was wave soldering. Hot-air solder leveling (HASL) was the
finish of choice for component holed on the board. The evolution from
through-hole components to surface-mount components offered great opportunities
to reduce the size and weight of the final electronic product. Surface-mount
pads required screen pastes and reflow assembly. |
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Specifications |
Details |
| Finish Plating |
Solder(HASL), Lead Free Solder(HASL), ENIG (ELectroless
Nickel Immersion Gold), OSP, Immersion Silver, White Tin, Immersion Tin,
Immersion Nickel, Hard Gold, Other |
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| Final PCB Fabrication Test |
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Advances in packaging technology resulting in finer board geometry, including
the various forms of high-density interconnection (HDI), have combined with
increasing data rates to put significant pressure on the electrical test area.
Fixture construction is more expensive and requires improved process control. |
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