Patent ID: 11929334
Assignee: STATS CHIPPAC PTE. LTD.
Field: Semiconductors (Electrical engineering)
Classification: CPC H  B | IPC B  H

Claim 11:
12. A method of making a semiconductor device, comprising:
generating a calibration equation by,
disposing a beam homogenizer in a first position over a semiconductor die with a beam of the beam homogenizer shining onto the semiconductor die,
capturing a first image of the semiconductor die and beam with the beam homogenizer in the first position over the semiconductor die,
calculating a first positional offset of the beam relative to the semiconductor die in a first number of pixels by using image processing on the first image,
moving the beam homogenizer a known distance to a second position over the semiconductor die,
capturing a second image of the semiconductor die and beam with the beam homogenizer in the second position over the semiconductor die,
calculating a second positional offset of the beam relative to the semiconductor die in a second number of pixels by using image processing on the second image, and
performing a linear regression with the known distance, first number of pixels, and second number of pixels;

returning the beam homogenizer to the first position over the semiconductor die;
capturing a third image of the beam f light and semiconductor die;
performing image processing on the third image, wherein the image processing includes,
determining a first boundary of the semiconductor die,
determining a second boundary of the beam of light, and
comparing the first boundary and second boundary in the image to determine a number of pixels by which the first boundary and second boundary are out of alignment;

using the calibration equation to convert the number of pixels into a distance and thereby center the first boundary of the semiconductor die completely within the second boundary of the beam of light; and
using the beam to melt a solder bump of the semiconductor die after using the calibration equation to center the first boundary within the second boundary.