The present invention relates to a carrier for electronic components, comprising a panel which is substantially flat and at least partially subdivided into segments, which segments are partially bounded by recesses in the panel. The invention also relates to a method for separating segments from a carrier for electronic components.

Large-scale use is made of carriers for electronic components, particularly though not exclusively during the production of semiconductor circuits. Such carriers are also referred to as "leadframe" or "board", and can consist of a single metal layer (for instance a copper layer) or of a laminated sheet material. A collective carrier makes it possible to efficiently process a plurality of circuits on a shared carrier and, owing to the shared carrier, manipulation of the ultimately usually very small individual products represents less of a problem during collective processing of a plurality of mutually connected products. After running through one or more processing steps the segments are then individualized, i.e. separated or detached from each other. It is herein possible for the carrier to be wholly subdivided- into such segments, but it is also possible for the segments to be separated from a remaining connecting structure. This subdivision usually takes place with a punching operation or a machining technique, such as for instance sawing. The existing separation of the individual segments is a relatively costly process which cannot always be performed with sufficient precision and/or reliability.

The object of the present invention is to provide an improved carrier for electronic components from which segments can be separated in simplified manner. The invention also has for its object to provide an improved method for separating segments from such a carrier, with which the separating operation can be performed rapidly and reliably compared to the prior art.

The invention provides for this purpose a carrier for electronic components comprising a panel which is substantially flat and at least partially subdivided into segments, which segments are partially bounded by recesses in the panel, characterized in that the segments are bounded by at least one recess such that all boundary lines with which an individual segment connects to the remaining part of the panel are parallel to each other. It is noted that a segment may also be connected to the remaining part of the carrier with only a single boundary line, but this is less likely to occur in practice because such a coupling with a single boundary line results in a less stable anchoring of the segment in the carrier. A boundary line is an imaginary line at the position of a connecting part between the segment and the remaining part of the carrier.

The carrier will usually be subdivided, into a number of segments which are placed in a matrix structure and which connect to a connecting grid likewise consisting of carrier material. It is advantageous if all boundary lines of all segments forming part of the carrier are parallel to each other. The parallel state of the boundary lines makes it possible to separate the segments in relatively simple manner because the relative movement between a separating element (blade, saw, milling cutter, laser beam and so forth) and the carrier can be continuous; and, if the connecting boundary lines are straight, can itself be straight. An even further simplification of the separating operation can be realized if the boundary lines of adjoining segments lie mutually in line; connections of a plurality of segments can now be successively broken by a single continuous relative movement. Continuous, preferably linear movements can be realized quickly and reliably compared to movements which are not continuous. When a desired relative movement of the separating tool and carrier is not continuous (i.e. when the second derivative of the movement in time, d2x/dt2, is discontinuous) this causes problems in the case of a precise control and due to the mass inertia of the mutually displaceable components a slow-down in the separating speed will have to take place before the change of direction can be initiated and it is then possible to accelerate again to the separating speed. Consider here for instance a manipulator with which the carrier is moved and/or a movable separating member such as a cutting head. Another preferred value in respect of the continuous movement in the application according to the present invention is that the acceleration d2x/dt2 is nowhere more than 30 m/s2 during performing of a separating operation. Yet another preferred value for specifying the continuous movement more precisely is that the "jerk" of the separating operation must have a constant progression in time, or even more preferably is limited to values smaller than 200 m/s3. A prerequisite in respect of the continuous movement which evidently ensues from this latter (preferred) specification is that the acceleration of the separating movement must consist of a function which is continuous and can be differentiated. A segment usually consists of a rectangular part of the panel. Such a segment can advantageously connect on two opposite sides to the remaining part of the panel. Such a segment can form part of the carrier in sufficiently strong manner, while the advantages of a simplified separation are nevertheless provided.

In practice the segments are separated only after diverse processes have been performed on the carrier. A segment can thus be provided with at least one electronic component, in particular an integrated circuit or a semiconductor. Placing of the electronic components can then take place in the situation where the segment is still embedded in the carrier, which simplifies placing. It is also advantageous if the encapsulation of the electronic component takes place in a situation where the segment is still embedded in the carrier; the segment is then provided with an electronic component encapsulated with moulding material (usually epoxy).

The invention also provides a method for separating segments from a carrier for electronic components, wherein boundary lines with which the segments connect to the remaining part of the panel are broken via a desired separating route which is defined by at least one continuous, preferably linear, separating movement. This method can be performed with great precision using relatively simple means (a simple separating device because control of the relative movement of separating tool and carrier is simple), so that separation of the segments can be performed with high quality at relatively low cost. For the further advantages of this method reference is made to the foregoing, already described advantages of the carrier according to the present invention.

Further optimization of the method can be obtained by separating the segments by a plurality of parallel separating movements. The method is further found to be particularly advantageous when the separating movement consists of a mutual displacement of a carrier for electronic components and a laser beam, although it is of course also possible to apply the method in combination with a machining tool.

The present invention will be further elucidated on the basis of the non-limitative exemplary embodiments shown in the following figures. Herein: figure 1 shows a view of a carrier according to the invention, figure 2 shows a view of an alternative embodiment variant of a carrier according to the invention, figure 3 shows a view of a part of a second embodiment variant of a carrier according to the invention, and figure 4 shows a view of a part of a third embodiment variant of a carrier according to the invention.

Figure 1 shows a carrier 1 in which recesses 2, 3 are left clear such that segments 4 are partially released from a grid 5 connecting the segments 4. Recesses 2, 3 are arranged such that for full separation of segments 4 and grid 5 it is only necessary to make linear cuts 6 which are shown in broken lines and which are all parallel to each other.

Figure 2 shows a carrier 10 with recesses 11 which are U-shaped. Segments 13 can also be released in this carrier 10 using parallel cuts 12. Segments 13 are provided with an electronic component protected with encapsulating material 14.

Figure 3 shows a part of a carrier 20 in which a recess 21 is arranged such that a segment 22 is connected on only one side to the remaining part of carrier 20, so that these segments can be separated with parallel linear cuts 23.

Figure 4 finally shows a part of a carrier 30 in which a recess 31 is arranged such that a segment 32 can be released from the remaining part of carrier 30 with circle segment- like cuts 33. While these cuts 33 are not linear, they can still be arranged with a continuous (and therefore readily controlled) movement. Such a segment 32 will be applied particularly for carrying electronic components with high power dissipation.