Method for positioning a carrier with electronic components and electronic component produced with such method

Abstract

The present invention relates to a method of processing a solder masked carrier with electronic components, comprising the detection of a carrier related reference and the detection of a solder mask dependent reference, which detected reference are used for processing the position of the solder mask on the carrier. The invention also relates to an electronic component as produced with such method.

Claims

1. A method of processing a solder masked carrier with electronic components, comprising the method steps: A) detecting at least one carrier related reference; B) processing the at least one detected carrier related reference into a position of the carrier; C) detecting at least one solder mask dependent reference; and D) processing the at least one detected solder mask dependent reference into a position of the solder mask on the carrier, thereby detecting inaccuracies in the positioning of the solder mask to the carrier; wherein the method further comprises the method step of E) processing the solder masked carrier with electronic components dependent on the position of the solder mask as such on the carrier, thereby compensating for the inaccuracies in the positioning of the solder mask to the carrier; and wherein the processing of the solder masked carrier with electronic components according step E) comprises the separation of the solder masked electronic components.

2. The method as claimed in claim 1, wherein the separation of the solder masked electronic components comprises the sawing of the solder masked carrier with electronic components.

3. The method as claimed in claim 1, wherein the processing steps A) and C) are combined in a single detection step.

4. The method as claimed in claim 1, wherein the solder mask is applied to the carrier before the processing steps A)-E) take place.

5. The method as claimed in claim 1, wherein a functional board part is detected as a carrier related reference.

6. The method as claimed in claim 1, wherein the method also comprises the method step of attaching contacts to the solder masked carrier.

7. The method as claimed in claim 1, wherein the processing of the solder masked carrier with electronic components according step E) involves the at least partial electronic isolation of the electronic components.

8. The method as claimed in claim 1, wherein the processing of the solder masked carrier with electronic components according step E) is steered dependent on the processed position of the solder mask on the carrier according step D).

9. The method as claimed in claim 1, wherein in subsequent manipulations of the processing of the solder masked carrier with electronic components according step E) new carrier and/or solder mask dependent references are detected.

10. The method as claimed in claim 1, wherein during detection of a least one solder mask dependent reference the solder masked carrier is lighted with co-axial light.

11. The method as claimed in claim 1, further including: F) detecting new carrier and/or solder mask dependent references in subsequent manipulations of the processing of the solder masked carrier with electronic components.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The present invention will be further elucidated on the basis of the non-limitative exemplary embodiments shown in the following figures. Herein shows:

(2) FIGS. 1A and 1B perspective views on carriers with electronic components before and after a solder mask has been applied onto the carrier;

(3) FIGS. 2A and 2B top view on a detail of a carrier related reference and a solder mask dependent reference;

(4) FIGS. 3A-3C side views, on a carrier with electronic components, once before a solder mask has been applied onto the carrier, and twice after solder mask have been applied as well as solder balls have been attached;

(5) FIG. 4 a top view of a solder mask applied to a carrier with electronic components; and

(6) FIGS. 5A-5C show different mutual positions of a component and a PCB after separation but prior to further processing.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

(7) FIG. 1A shows a perspective view on carrier 1 which is provided from a pattern 2 of wiring and contact pads (seen only in general and indicated by the grey area's 3). On the carrier 1 are also carrier related references 4 that are often affixed together with the wiring and contact pads. In FIG. 1A is also shown that a vision camera 5 detects the carrier related references 4.

(8) FIG. 1B shows a perspective view on the carrier 1 from FIG. 1A but now after a solder mask 6 has been added to the carrier 1 leaving locally only minor openings free to enable the placing of contacts as will be explained in connection to FIGS. 3A-3C and 4. In FIG. 1B again a vision camera 7 is shown now for the detection of solder mask dependent references as will be explained in connection to FIG. 2B. In stead of detecting the carrier related references 4 before the solder mask 6 has been added to the carrier 1 the present invention also covers the detection of the carrier related references 4 after the solder mask 6 has been added to the carrier 1. In practise this will even be more usual than the detecting the carrier related references 4 before the solder mask 6 has been added to the carrier 1.

(9) FIG. 2A shows a top view on a carrier related reference 10 by the detection of which information gets available on the position of a carrier 11 on which the carrier related reference 10 is placed. FIG. 2B shows in top view a reference 12 which is placed on a carrier 13 but which is partially covered by a solder mask 14. In the solder mask 14 an opening 15 is left blank. When detecting the reference 12 in combination with detection of the location of the opening 15 relative to the reference 12 a solder mask dependent reference is obtained however as explained already in reference to FIGS. 1A and 1B it is also possible according the present invention to detect the carrier related reference 10 after the carrier 13 is partially covered by the solder mask 14.

(10) FIG. 3A shows a side view on a carrier 20 with a contact pad 21. In FIG. 3B a solder mask 22 is placed on the carrier 20 and a (solder) ball 23 is subsequently placed on top of the contact pad 21. The same situation is shown in FIG. 3B where a solder mask 24 is placed on the same carrier 20 and also here a (solder) ball 25 is subsequently placed on top of the contact pad 21. The solder mask 22 in FIG. 3C is placed more to the left than the solder mask 24 in FIG. 3C. Dependent on the specific measurements the position of the solder mask 22, 24 may also influence the position of the solder balls 23, 25. The solder ball in FIG. 3B is placed more to the left than the solder ball 25 shown in FIG. 3C as the openings in the solder masks 22, 24 are such that they dictate the position of the balls. These FIGS. 3B and 3C show that knowledge of the relative position of the solder masks 22 and 24 provides information on the subsequent positioning of solder balls 23, 25.

(11) FIG. 4 shows a top view of a solder mask 30 applied to a carrier 31 with electronic components. The solder mask 30 is provided with a grid of apertures 32 that are open to accept solder balls (not shown here) to be place. The X/Y positioning of the solder mask 30 (shift in two directions) may thus be relevant for the positioning of solder balls still to be placed in the situation as shown in FIG. 4.

(12) FIGS. 5A-5C show different mutual positions of a component and a PCB, prior to further processing. FIG. 5A shows a theoretical optimal position of a component 40 with solder balls 41, correctly positioned with respect to contact pads 42.

(13) FIG. 5B shows a practical situation, wherein there is a difference 43 between the centre of the solder ball 41 and the contact pad 42. The difference 43 logically also occurs between the solder ball 41 and the contact pad 45 of a PCB 44, that is outlined with the component, without applying an anticipating correction according to the present invention.

(14) FIG. 5C shows that, with the anticipation correction according to the present invention, solder ball 41 and PCB contact pad 45 are correctly outlined.

(15) According the present invention inaccuracies in the positioning of the solder mask to the carrier (or any carrier bound items like the electronic components and/or wiring on the carrier) are detected and as far as the influence the accuracy of the processing of the solder masked board can be compensated in the processing of the solder masked carrier. An example of such wiring detection is the detection of bus lines on semiconductor carriers. These bus lines provide electronic connections between the semiconductors that should be severed in a later process. In case of inaccuracy in the positioning of these bus lines later isolation of the semiconductors could be frustrated leading to higher rejection levels. The inaccuracy of the solder mask positioning on the carrier (also referred to as solder mask shift) can according the present invention however be taken out of the processing accuracy of the solder masked board.