PCB Classify: Rigid PCB Single-sided, double-sided & multi-layer
PCB (up to *0 layers) HDI,High TG
Multilayer,Heavy Copper,Gold Finger,Blind Buried Holes
PCB,Impedance PCB and other special
process. Flexible & Rigid-flex
PCB Flexible PCB (up to *0 layers) & Rigid-flex
PCB (up to 8 layers) Metal Core PCB Single/Double-Sided Aluminium Base PCB and
Copper Base PCB PCB Material CEM*1,CEM*3,FR*4,High TG,Polyimide, Aluminum
and Copper-based material. PCB Surface Technics HAL, HAL lead free, Immersion Gold/ Silver/Tin,
Hard Gold, OSP
Multilayer PCB
Introduction: The manufacturing method of the multilayer PCB
board is generally performed by the inner layer pattern first, and
then the single-sided or double-sided substrate is formed by the
printing etching method, and is incorporated into the specified
interlayer, and then heated, pressurized and bonded, and the
subsequent drilling is performed. Holes are the same as
double-sided plated through holes Plated through hole Once copper After the formation of the via hole in the
interlayer, it is necessary to build a copper layer on it to
complete the conduction of the interlayer circuit. Firstly,
brushing and high-pressure flushing are used to clean the dust on
the holes and pores, and then remove the smear on the copper
surface of the pore wall with potassium permanganate solution. A
tin-palladium colloid layer is immersed in the cleaned pore wall
and then reduced to metallic palladium. The circuit board is
immersed in a chemical copper solution, and palladium ions in the
solution are used to reduce the copper ions in the solution and
deposit on the wall of the hole to form a via circuit. Then, the
copper layer in the via hole is thickened by a copper sulfate bath
to sufficiently resist the thickness of the subsequent processing
and use of the environmental impact. Outer line Secondary copper In the production of circuit image transfer
printing, it is similar to the inner layer circuit, but in the line
etching, it is divided into two kinds of production methods:
positive and negative. The production method of the negative film
is the same as that of the inner layer circuit. After the
development, the copper is directly etched and the film is removed.
The production method of the positive film is to apply the
secondary copper and tin-lead plating after the development (the
tin-lead in this area will be retained as an etching resist in the
later copper etching step), and the film will be alkaline after the
film is removed. Aqueous ammonia and copper chloride mixed solution
etch away the exposed copper foil to form a circuit. Finally, tin
and lead stripping solution was used to strip the tin and lead
layers that had been retired. (In the early days, there were tin
and lead layers that had been reserved, and after being used as a
cover layer, they were used as a house-keeping layer. Now, they are
not needed.) . Anti-welding edge paint After the outer layer circuit is completed, it
needs to be covered with an insulating resin layer to protect the
household circuit from oxidation and welding short circuit. Before
the coating, the copper surface of the circuit board must be
properly roughened and cleansed by brushing and micro-etching.
Afterwards, the liquid photosensitive green paint is applied to the
board surface by means of steel plate printing, curtain coating,
electrostatic spraying, etc., and then pre-baked and dried (dry
film photosensitive green paint is laminated by a vacuum laminator.
On the board). When it is cooled, it is sent to an ultraviolet
exposure machine for exposure. The green paint will produce a
polymerization reaction after being exposed to ultraviolet rays in
the light-transmitting area of the film (the green paint in this
area will be retained in a later development step), with a solution
of sodium carbonate. Undeveloped areas of the film were developed
and removed. Finally, high-temperature baking was performed to
completely harden the resin in the green paint. skype: oneseine-sales
