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In this study addresses the core multilayer organic circuit substrate in the probe card, the circuit substrate surface contains a layer of green solder mask, used to distinguish signals, but because of the circuit’s tiny circuit, causes the solder mask to be indistinguishable and protect the circuit, so the circuit board is forced to design the exposed wire, make the probe and multi-layer organic circuit board at the time of signal transmission, may cause wire damage, make probe card life greatly reduced, affect product yield detection, to extend probe card life, use of exposure and development techniques in MEMS processes, protecting multi-layered organic circuit boards exposed copper wire, the contact signal appears, use of electrochemical reactions to produce copper wire, finish the plane with grinding, focused on this study.
Exposure development process, in the structure with a height difference of 25μm, make about 2000 hole structures, photoresist structure with diameter of 25μm and depth of 35μm, and filling copper metal with electrochemical reaction, as a wire, causes the exposed copper wire on the multilayer organic circuit board to be protected, and individual independence, contact with the probe.This process uses positive photoresist AZ4620, finally using chemical mechanical polishing, flatten the conductors with 25μm gap between the circuit board, fully flattened leads, it also protects the bare copper wire, allows the probe to more stably contact the board with each individual signal point, effectively reduce the probability of probe card failure and prolong service life.
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