Method and apparatus for detecting deformations of leads of semiconductor device

Claim 1

A method of detecting horizontal and/or vertical deformation of leads of a semiconductor device, comprising steps of: illuminating leads (20) of the semiconductor device (11) with a planar light beam (14); picking up images of regions (22a, 22b) of said leads (20) illuminated with said planar light beam (14) by means of image pick-up means (13); and detecting at least one of the vertical deformation and the horizontal deformation of said lead on the basis of distributed data (Fig. 10) of said illuminated regions (22a, 22b) of the individual leads (20) picked up by said image pick-up means (13).

Claim 4

A method of detecting horizontal and/or vertical deformation of lead of a semiconductor device, comprising steps of: illuminating leads (20) of a semiconductor device (11) with a planar light beam (14); picking up images of regions (22a, 22b) of said leads (20) illuminated with said planar light beam (14) by means of image pick-up means (13); arithmetically determining statistically weighted average positions (X(J)) of the illuminated lead regions (22a, 22b) picked up by said image pick-up means (13); and detecting at least one of vertical deformation and horizontal deformation of said leads on the basis of distribution of said statistically weighted average positions.

Claim 5

A method of detecting lead deformations in a semiconductor device, comprising: a step of illuminating leads (20) of a semiconductor device (11) with a planar light beam (14); a step of picking up images of the leads (20) illuminated with said planar light beam (14) by means of image pick-up means (13) and binary-coding image data of the regions (22a, 22b) of said leads illuminated with said planar light beam (14) and outputted from said image pick-up means (13); a step of determining the regions (22a, 22b) of the individual leads (20) illuminated with said planar light beam (14) on the basis of the binary coded image data and determining lines (24) each passing through a center position of each of said regions illuminated with said planar light beam; a step of determining statistically weighted average positions (X(J)) in respect to brightness of said regions illuminated with said planar light beams relative to said line (24); a step of approximating the distribution of the statistically weighted average positions of said illuminated regions by a straight line (25); a step of drawing perpendiculars to said statistically weighted average positions, respectively, from said approximate straight line (25); and a step of determining distances to said statistically weighted average positions, respectively, from said approximate straight line (25).

Claim 6

A method of detecting lead deformations in a semiconductor device, comprising: a step of illuminating leads (20) of a semiconductor device (11) with a planar light beam (14); a step of picking up images of the leads (20) illuminated with said planar light beam (14) by means of image pick-up means (13) and binary-coding image data of the regions of said leads illuminated with said planar light beam (14) and outputted from said image pick-up means; a step of determining regions of the individual leads (20) illuminated with said planar light beam (14) on the basis of the binary coded image data and determining lines (24) each passing through a center position of each of said regions illuminated with said planar light beam; a step of determining statistically weighted average positions in respect to brightness of said regions illuminated with said planar light beams relative to said line (24); a step of approximating the distribution of the statistically weighted average positions of said illuminated regions by a straight line (25); a step of drawing perpendiculars to said statistically weighted average positions, respectively, from said approximate straight line (25); and a step of determining distances (K') between adjacent ones of said perpendiculars, respectively, to thereby determine magnitude of the vertical deformation of the leads of said semiconductor device.

Claim 7

A method of detecting lead deformation in a semiconductor device, comprising: a step of illuminating leads (20) of a semiconductor device (11) with a planar light beam (14); a step of picking up images of the leads (20) illuminated with said planar light beam (14) by means of image pick-up means (13) and binary-coding image data of the regions of said leads illuminated with said planar light beam (14) and outputted from said image pick-up means; a step of determining regions (22a, 22b) of the individual leads (20) illuminated with said planar light beam (14) on the basis of the binary coded image data and determining lines (24) each passing through a center position of each of said regions illuminated with said planar light beam; a step of determining statistically weighted average positions in respect to brightness of said regions illuminated with said planar light beams relative to said line (24); a step of approximating the distribution of the statistically weighted average positions of said illuminated regions by a straight line (25); a step of drawing perpendiculars to said statistically weighted average positions, respectively, from said approximate straight line (25); a step of determining distances to said statistically weighted average positions, respectively, from said approximate straight line (25); and a step of determining distances (K') between adjacent ones of said perpendiculars, respectively, to thereby determine magnitude of the vertical deformation of the leads of said semiconductor device.

Claim 8

An apparatus for detecting deformations of leads of a semiconductor device, comprising: planar light beam generating means (15, 16) for illuminating the leads (20) of the semiconductor device (11) with a planar light beam (14); image pick-up means (13) for picking up images of said leads (20) to thereby output image signals; and image processing means (19) for processing said image signals.

Claim 9

An apparatus for detecting deformations of leads of a semiconductor device according to claims 8, wherein an angle of an optical axis along which said planar light beam (14) is projected onto soldering surfaces of said leads is selected smaller than 90°, and an angle (Θ) between said optical axis of said planar light beam and that of said image pick-up mean (13) is selected approximately 90°.

Claim 10

An apparatus for detecting deformations of leads of a semiconductor device according to claims 8, wherein said image processing means (19) is imparted with a function for arithmetically determining statistically weighted average positions of the planar light beam (14) on said individual leads (20) on the basis of said image signals, to thereby detect at least one of vertical and horizontal deformations of said leads on the basis of said statistically weighted average positions.

Claim 11

An apparatus for detecting deformations of leads of a semiconductor device according to claims 8, wherein said planar light beam generated by said planar light beam generating means (15, 16) is monochromatic, and wherein said image pick-up means picks up images of the leads (22) of the semiconductor device (11) through a filter (23) which passes therethrough only those light rays which result from reflection of said monochromatic planar light beam on said leads (22).