US 4,980,971 A · Method and apparatus for chip placement

Abstract

A system (10) for precisely placing a semiconductor chip (16) on a substrate (11) includes a robotic arm (18) which is provided with a gripper (22) for separately picking up the chip and substrate. A first television camera (38) is carried by the robotic arm and serves to capture the image of the substrate to locate a pair of datum points (71a and 71b) thereon. A second camera (40), stationary with respect to the robotic arm, serves to capture the image of the chip (16), when engaged by the robot, to locate each of a pair of datum points (83a and 83b) thereon. A machine vision system (46) serves to process the output signal of the cameras (38) and (40) to establish the precise location of the datum points on the substrate and on the chip. The information from the vision system (46) is employed to control the robotic arm to cause the gripper to place the chip on the substrate such that each of the datum points on the substrate is at a prescribed location relative to a separate one of the datum points on the chip.

Claims12

Dependent claims

A method of fabricating an object with an article placed thereon using a system comprised of a movable gripping device and a pair of cameras, the first camera mounted to the gripping device for movement therewith, and the second camera being stationary, the method comprising the steps of:

calibrating the system to establish the location and orientation, relative to the gripper, of a reference pixel in the field of view of each of the first and second cameras;
displacing the gripper to successively locate the reference pixel in the field of view of the first camera in substantially exact registration with each of a pair of datum points on the object to establish the location of the object;
engaging the article with the gripper;
displacing the gripper to successively locate the article in the field of view of the second camera so that each of a pair of datum points on the article is in substantially exact registration with a reference pixel in the second camera's field of view to establish the location of the article;
and
displacing the gripper to precisely place the article on the object such that each of the datum points on the article is in a prescribed relationship with a separate one of the datum points on the object.

3 more elements

A method of precisely placing a chip on a substrate with the aid of a gripper and a pair of cameras, the first mounted to the gripper to move therewith and the other camera being stationary, the method comprising the steps of:

(a) calibrating the system to estblish the location of a reference pixel in each camera relative to the frame of reference of the gripper;
(b) displacing the gripper to successively locate the reference pixel of the first camera in substantially exact registration with each of a pair of datum points on the substate to establish its location;
(c) engaging the substrate with the gripper;
(d) displacing the gripper to place the substrate in a chuck;
(e) engaging a chip with the gripper;
(f) displacing the gripper to displace the chip so that each of a separate one of a pair of datum points on the chip is successively placed in substantially exact registration with a reference pixel in the second camera's field of view to establish the location of the chip;
(g) displacing the gripper to place the chip on the substrate such that each datum point on the chip is in a prescribed relationship with a separate one of the datum points on the substrate;
and
(h) tacking the chip to the substrate.

6 more elements

Dependencies are inferred from the claim text.

Method and apparatus for chip placement

Life of this patent

Method and apparatus for chip placement

Life of this patent

Abstract

Claims12