Positioning arrangement and face down bonder incorporating the same

Claim 1

In a positioning apparatus for matching the relative positions of two components to be bonded or mated face-to-face together in registration including first and second holders which hold said two components in substantially parallel relationship, respectively, position adjusting means for moving at least one of said holders so as to move said components vertically and horizontally towards and away from each other in such a manner as to maintain a mutually parallel relationship therebetween, illumination means for illuminating said two components, respectively, a compound prism inserted between said first and second holders, said compound prism comprising a truncated quadrilateral prism of transparent material having a 45 degree truncation, a rectangular transparent prism having a surface subtending the rectangle thereof and united at the surface with the truncation of the truncated prism into a parallelopiped shape, a halfsilvered mirror film serving as a half-silvered mirror and formed at the interface between the truncated prism and the rectangular prism, and a totally reflective mirror film serving as a total reflector and provided on one of the two mutually perpendicular surfaces of the rectangular prism, said one of the two surfaces being opposite to a side of the truncated prism and the other one forming a top of the compound prism which is opposite to the base of the truncated prism, and said total reflector being perpendicularly positioned relative to the two components and facing the half-silvered mirror film with an angle of 45* therebetween, and imaging means provided in substantial alignment with the total reflector on the other side of the half-silvered mirror therefrom for forming images of the two components superposed on each other, the improvement which comprises: two half-silvered illumination mirrors provided between said compound prism and said first and second holders, respectively, at an angle with respect to the top and the base of the compound prism; light source means for projecting light onto the respective components through said two half-silvered illumination mirrors, respectively, whereby said half-silvered illumination mirrors and said light source means form said illumination means, so that vertical illumination is provided onto the two components; pick-up means for picking up one component from its holder positioned above the compound prism, said pick-up means being mounted for movement up and down with respect to the other one of said components fixed in relation thereto; means for removing said compound prism and the holder for said one component out of the position between the two components and for reinserting said compound prism and the holder in the position; a compensating prism provided in a position between said compound prism and one of the two components for compensating for residual deviation of the compound prism as well as mechanical error of the apparatus.