Punch actuator monitoring system and method

#The present invention relates to forming holes in a substrate. In particular, the present invention relates to mechanically punching holes in films, especially thin films for use in the electronics industry. More particularly, the present invention relates to a method and apparatus for ensuring hole quality and minimizing or eliminating damage to the films during the hole punching process.

#Some aspects of the fabrication of structures for use in the electronics industry require the formation of holes in a substrate. One method for forming such holes is to physically punch the holes in the substrate. Typically, the substrates are thin films.

#Frequently, the punching of holes occurs while the punching device and the substrate move relative to each other. The movement of the punching device and the substrate may take place in both the X and Y directions. That is, movement may take place parallel to the plane of the substrate. Such movements along the axial directions are referred to as “punch-on-the-fly X” (POFX) and “punch-on-the-fly Y” (POFY).

#FIG. 1 represents a cross-sectional view of a die bar assembly for punching holes in a substrate;

#FIG. 2 represents a close-up view of an embodiment of a punch, driven by electromagnetic repulsion, in the die bar assembly according to the present invention;

#FIG. 3 represents a graph illustrating voltage versus time for the output of an accelerometer during one punch actuation cycle; and

#As discussed above, the present invention relates to mechanically punching holes in substrates. The present invention is particularly useful for preventing damage to substrates when mechanically punching holes in the substrates. In particular, the present invention is particularly useful for preventing damage to substrates used in the electronics industry. The present invention permits precise punching of minute, closely spaced apertures without improper aperture shape distortion and without destroying the substrate in which the apertures are formed.

#For example, the present invention is particularly useful in preventing damage to thin substrates, such as thin dielectric film used in the electronics industry. Examples of such films include polyimide films. Such films are used to fabricate highly dense, circuitized substrates, such as thin, flexible circuits. Of course, the present invention may be utilized to form holes in any substrate.

#FIG. 1 shows a cross-sectional view of an embodiment of a die bar assembly according to the present invention which may be utilized to punch holes in a substrate. The apparatus shown in FIG. 1 includes an upper die bar 1. The upper die bar houses a plurality of punches 3 that actually physically punch holes in a substrate. The substrate passes between the upper and lower portions of a die bar during the punching operation.