Print solder paste fixture and use this fixture to repair the method for surface-mounted integrated circuit
Technical field
The present invention relates to a kind of fixture that chip is fixed when the print solder paste relates in particular to a kind of print solder paste fixture and uses this fixture to repair the method for surface-mounted integrated circuit.
Background technology
The nineties in 20th century is along with the progress of integrated technology, the improvement of equipment and the use of deep sub-micron technique, large scale integrated circuit, very lagre scale integrated circuit (VLSIC), great scale integrated circuit occur in succession, silicon single-chip integrated level improves constantly, require stricter to integrated antenna package, the I/O number of pins sharply increases, and power consumption also increases thereupon.Be to satisfy the needs of development, on original encapsulation kind basis, increased again BGA Package, be called for short BGA (Ball Grid Array Package).The nineties in 20th century, chip integration improved constantly along with the progress of technology, and the I/O number of pins sharply increases, and power consumption also increases thereupon, and is also stricter to the requirement of integrated antenna package.In order to satisfy the needs of development, the BGA encapsulation begins to be applied to produce.BGA is the abbreviation of English Ball Grid Array Package, i.e. BGA Package.Adopt the internal memory of BGA technology encapsulation, can make internal memory in the situation that the constancy of volume memory size improves two to three times, BGA has less volume, better heat dispersion and electrical property.The BGA encapsulation technology makes memory space per square inch that very large lifting arranged, adopt the internal memory product of BGA encapsulation technology under same capability, chip than other packaged types has less volume, in addition, compare with the conventional package mode, the BGA packaged type has quicker and effective heat radiation approach.The I/O terminal of BGA encapsulation is distributed in below encapsulation by array format with circle or column solder joint, has increased although the advantage of BGA technology is the I/O number of pins, and pin-pitch does not reduce to have increased on the contrary, thereby has improved assembly yield; Although its power consumption increases, BGA can weld with the control collapsed chip method, thereby can improve its electric heating property; Thickness and weight all than before encapsulation technology reduce to some extent; Parasitic parameter reduces, and signal transmission delay is little, and frequency of utilization improves greatly; Assemble available coplanar welding, reliability is high.
In production and debug process, unavoidably can be because BGA damages or other reasons replacing BGA.BGA reclamation work station can be completed the work of dismounting BGA equally.Dismounting BGA can be regarded as the reverse process of welding BGA.Difference is, after temperature curve is complete, BGA siphoned away with vacuum WAND, and why without other instruments, such as tweezers, be because will avoid because exert oneself excessive damage pad.The PCB that takes off BGA is carried out the detin operation while hot, why to operate while hot? because the PCB of heat is suitable and the function of preheating, can guarantee that the work of detin is more prone to.Then weld new BGA.In the prior art field, welding new BGA, the step of a key is arranged is to plant ball, and the purpose of planting ball is exactly that the tin ball is implanted on the pad of BGA again, can reach and the new same arrangement effect of BGA, and the PCB that reprocesses is not often only a few.Present circuit board integrated level is high, and the part of periphery is separated by too near, on finished circuit board print solder paste very because of difficulty, and larger to the product local lesion when repairing.
Therefore need badly a kind of can reduce repair difficulty and repair cost, solution reprocessing print solder paste on circuit board difficult, reduce and repair the print solder paste fixture of product local lesion degree and use this fixture to repair the method for surface-mounted integrated circuit.
Summary of the invention
One of purpose of the present invention be to provide a kind of can reduce repair difficulty and repair cost, solution reprocessing on circuit board print solder paste difficult, reduce the print solder paste fixture of repairing product local lesion degree.
Another object of the present invention be to provide a kind of can reduce repair difficulty and repair cost, solution reprocessing on circuit board print solder paste difficult, reduce the method for repairing the repairing surface-mounted integrated circuit of product local lesion degree.
To achieve these goals, a kind of print solder paste fixture of the present invention, be used for chip is fixed when the print solder paste, it comprises supporting bracket, the front of described supporting bracket offers some chip containing groove, and the back side that the bottom land of described chip containing groove runs through described supporting bracket offers the corresponding pin bores of pin with chip appearance.
Preferably, the back side of described supporting bracket is recessed to form the brush molten tin bath over against described chip containing groove place, and described pin bores runs through described brush molten tin bath and described chip containing groove.Described brush molten tin bath splendid attire tin cream preferably is set in the back side of described supporting bracket, prevents from causing the waste of tin cream when saving operation.
Preferably, convex with raised line in described chip containing groove.Described raised line is set can conveniently be taken out chip from described chip containing groove inner clip.
The present invention repairs the method for surface-mounted integrated circuit, comprises the steps:
(1) impaired old chip on surface-mounted integrated circuit is taken off from surface-mounted integrated circuit;
(2) chip containing groove of new chip being put into the print solder paste fixture fixes and the pin of new chip is passed pin bores;
(3) to the pin of the new chip that the passes pin bores back up tin cream in supporting bracket;
The new chip that (4) will be printed with tin cream takes out from chip containing groove;
The new chip that is printed with tin cream that (5) will take out is mounted on the position of former chip on surface-mounted integrated circuit and carries out the circuit welding;
(6) new chip that connects of butt welding carries out the transmission inspection;
(7) judge whether the transmission check result meets the requirements, if undesirable circulation is carried out above-mentioned steps (1)-(6) until the transmission check result meets the requirements.
Preferably, the transmission inspection in described step (6) is roentgen-ray transmission inspection.The penetration power of roentgen-ray is stronger, and the situations such as the solder skip of observing chip that can be more clearly, rosin joint and empty weldering are in time made and being remedied.
Compared with prior art, in print solder paste fixture of the present invention, the back side that the bottom land of described chip containing groove runs through described supporting bracket offers the corresponding pin bores of pin with chip appearance.Therefore, only need to put into new chip in described chip containing groove, the pin of new chip stretches into described pin bores to the back side of described supporting bracket, only need to brush tin cream at the back side of described supporting bracket, then new chip is taken out, tin cream will be stayed on the pin of new chip automatically, complete easily the brush process of tin of new chip.Therefore, reduced repairing difficulty and the repair cost of surface-mounted integrated circuit, solved and reprocessed print solder paste difficulty on circuit board, reducing and repair product local lesion degree.
By following description also by reference to the accompanying drawings, it is more clear that the present invention will become, and these accompanying drawings are used for explaining embodiments of the invention.
Description of drawings
Fig. 1 is the structural representation of an embodiment of print solder paste tool of the present invention.
Fig. 2 is the structural representation that print solder paste tool of the present invention is inserted new chip.
Fig. 3 is the view of another angle of print solder paste tool shown in Figure 1.
Fig. 4 is the zoomed-in view of tin cream tool A part on chip shown in Figure 1.
Fig. 5 is the zoomed-in view of tin cream tool B part on chip shown in Figure 3.
Fig. 6 is the flow chart that the present invention repairs the method for surface-mounted integrated circuit.
Embodiment
With reference now to accompanying drawing, describe embodiments of the invention, in accompanying drawing, similar element numbers represents similar element.As mentioned above, as shown in Fig. 1-5, print solder paste fixture 100 provided by the invention, it comprises supporting bracket 10, and the positive 10b of described supporting bracket 10 offers four chip containing groove 11, and the back side 10a of described supporting bracket 10 is recessed to form brush molten tin bath 15, described brush molten tin bath 15 and described chip containing groove 11 over against, the bottom land of described chip containing groove 11 offers pin bores 13, and described pin bores 13 runs through the back side 10a of described supporting bracket 10, and described pin bores 13 with appearance chip pin corresponding.Particularly, described pin bores 13 runs through described brush molten tin bath 15 and described chip containing groove 11.In the back side of described supporting bracket 10 10a, described brush molten tin bath 15 splendid attire tin cream preferably is set, reaches the waste that prevents from causing tin cream when repeatedly operation is saved in printing.The preferably as Fig. 1, Fig. 2 and shown in Figure 4, convexes with raised line 14 in described chip containing groove 11.Described raised line 14 is set can conveniently be taken out described chip 20 from described chip containing groove 11 inner clips.Can be with tweezers or sorption pen in the operation of reality with described chip 20 from the interior taking-up of described chip containing groove 11.
As described in Figure 6, the present invention repairs the method for surface-mounted integrated circuit, comprises the steps:
S001 takes off impaired old chip on surface-mounted integrated circuit from surface-mounted integrated circuit;
The chip containing groove that S002 puts into the print solder paste fixture with new chip fixes and the pin of new chip is passed pin bores;
S003 is to the pin of the new chip that the passes pin bores back up tin cream in supporting bracket;
The new chip that S004 will be printed with tin cream takes out from chip containing groove;
The new chip that is printed with tin cream that S005 will take out is mounted on the position of former chip on surface-mounted integrated circuit and carries out the circuit welding;
The new chip that the S006 butt welding connects carries out the transmission inspection;
S007 judges whether the transmission check result meets the requirements, if undesirable circulation is carried out above-mentioned steps S001-S006 until the transmission check result meets the requirements.
The preferably, the transmission inspection in described step S006 is roentgen-ray transmission inspection.The penetration power of roentgen-ray is stronger, and the situations such as the solder skip of observing chip that can be more clearly, rosin joint and empty weldering are in time made and being remedied.
In conjunction with Fig. 1-7, in print solder paste fixture 100 of the present invention, the back side 10a that the bottom land of described chip containing groove 11 runs through described supporting bracket 10 offers the corresponding pin bores 13 of pin with chip appearance.Therefore, only need to put into new chip 20 in described chip containing groove 11, the pin of new chip 20 stretches into described pin bores 13 to the back side 10a of described supporting bracket 10, only need to brush tin cream at the back side of described supporting bracket 10 10a, then new chip 20 is taken out, tin cream will be stayed on the pin of new chip 20 automatically, complete easily the brush process of tin of new chip 20.Therefore, reduced repairing difficulty and the repair cost of surface-mounted integrated circuit, solved and reprocessed print solder paste difficulty on circuit board, reducing and repair product local lesion degree.
Above invention has been described in conjunction with most preferred embodiment, but the present invention is not limited to the embodiment of above announcement, and should contain various modification, equivalent combinations of carrying out according to essence of the present invention.