Probe mark reading device and probe mark reading method
View Patent ↗A probe mark reading device for reading probe marks stormed on electrode pads of semiconductor chips contained in a semiconductor wafer ( 90 ), comprising a CCD camera ( 20 ) for taking an image of the semiconductor wafer ( 90 ) and outputting the image as an image signal Si, an optical unit ( 21 ) for optically enlarging a location to be photographed by the CCD camera ( 20 ), a light source ( 30 ) for illuminating the location to be photographed by the CCD camera ( 20 ) with a flash of light generated for a short period of time from when a flash signal Sf is provided, an X-Y stage ( 40 ) capable of changing a position to be photographed by the CCD camera ( 20 ) based on a motor control signal Sm by moving a mounted semiconductor wafer ( 90 ) in an X-direction and a Y-direction, and a computer ( 10 ) for providing control and saving the images after receiving and trimming the image signal Si. With the above configuration, it is possible to read probe marks in a short time without a user having to expend much time or effort.
1. A probe mark test device for checking probe marks formed on electrode pads during checking of electrical characteristics of a prescribed object including a plurality of electrode pads, comprising:
an initial vector calculator for calculating an initial vector equivalent to a vector drawn from a position of a pre-registered model probe mark relating to a prescribed reference electrode pad selected from the plurality of electrode pads to a position of a probe mark actually included in an image for the reference electrode pad obtained by photographing the reference electrode pad; and
a probe mark quality determination unit for determining whether or not a probe mark formed on an electrode pad different to the reference electrode pad is detected within a prescribed determination range including a position in the direction and distance of the initial vector from the position of the pre-registered probe mark relating to the different electrode pad.
2. A probe mark test method for checking probe marks formed on electrode pads during checking of electrical characteristics of a prescribed object including a plurality of electrode pads, comprising:
an initial vector calculating step of calculating an initial vector equivalent to a vector drawn from a position of a pre-registered model probe mark relating to a prescribed reference electrode pad selected from the plurality of electrode pads to a position of a probe mark actually including an image for the reference electrode pad obtained by photographing the reference electrode pad; and
a probe mark quality determination step of determining whether or not a probe mark formed on an electrode pad different to the prescribed reference electrode pad is detected within a prescribed determination range including a position in the direction and distance of the initial vector from the position of the pre-registered probe mark relating to the different electrode pad.
3. The probe mark test method of claim 2 , further comprising a probe mark position determination step of determining whether or not a probe mark overlaps with a prescribed region set for the vicinity of the edge of an electrode pad including the probe mark detected by the probe mark quality determination step.
4. The probe mark test method of claim 2 , further comprising a classification header generating step of generating classification header information including information identifying each electrode pad included in the object and determination results of the probe mark quality determination step and storing the classification header information correlating corresponding electrode pad images in a prescribed storage unit.
5. The probe mark test method of claim 2 , wherein the initial vector calculating step comprises:
a detection step of detecting probe marks formed by the electrical characteristic check by performing a difference operation on the images and images for the reference electrode pads taken in advance before checking the electrical characteristics; and
a calculating step of calculating an initial vector equivalent to the vector from the position of the probe mark taken as the pre-registered model correlating to the reference electrode pad to the position of the probe mark detected in the detection step.
6. The probe mark test method of claim 2 ,
wherein the initial vector calculating step is such that the initial vector is calculated based on the vector from the position of the probe mark that is the pre-registered model correlating to each of four reference electrode pads positioned in the vicinity of the corners of the object to the position of a probe mark formed on each of the reference electrode pads, and
the probe mark quality determination step is such that it is determined whether or not a probe mark formed on an electrode pad different to the four reference electrode pads is detected within a prescribed determination range including a position in the direction and distance of the initial vector from the position of the pre-registered probe mark relating to the different electrode pad.