U.S. patent number 3,765,431 [Application Number 05/131,393] was granted by the patent office on 1973-10-16 for apparatus for handling and maintaining the orientation of a matrix of miniature electrical devices.
Invention is credited to Frederick Joseph Jannett, Jaroslav Mracek.
United States Patent |
3,765,431 |
Jannett , et al. |
October 16, 1973 |
APPARATUS FOR HANDLING AND MAINTAINING THE ORIENTATION OF A MATRIX
OF MINIATURE ELECTRICAL DEVICES
Abstract
Grid is placed in channels of matrix of beam lead devices
cemented with soluble adhesive to plate. Grid-matrix-plate assembly
is drawn by vacuum onto first chuck with pattern of apertures at
one end. Solvent is forced through first chuck and apertures to
dissolve adhesive. Plate is removed and grid-matrix assembly
transferred to second chuck which may be porous block operable with
vacuum, magnetic block cooperating with magnetic grid, or a
combination thereof. Second chuck may also be magnetic block having
mesas and cooperating with magnetic grid, non-magnetic block having
apertures through mesas operable with vacuum, or combination
thereof. After transfer to second chuck, grid is removed and matrix
expanded.
Inventors: |
Jannett; Frederick Joseph (West
Millington, NJ), Mracek; Jaroslav (Lawrence Twp., Mercer
County, NJ) |
Family
ID: |
32232951 |
Appl.
No.: |
05/131,393 |
Filed: |
April 5, 1971 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
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886981 |
Oct 16, 1969 |
3681139 |
|
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Current U.S.
Class: |
134/113;
134/166R; 294/65.5; 134/155; 134/183; 248/363 |
Current CPC
Class: |
H01L
21/67 (20130101); H01L 2224/95144 (20130101) |
Current International
Class: |
H01L
21/67 (20060101); B08b 003/08 () |
Field of
Search: |
;134/113,137,154,155,165,166R,182,183,201 ;248/363 ;294/65.5 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Bleutge; Robert L.
Parent Case Text
CROSS REFERENCE TO RELATED APPLICATION
This application is a division of application Ser. No. 866,981
filed Oct. 16, 1969 and now U. S. Pat. 3,681,139.
Claims
What is claimed is:
1. Apparatus for holding a matrix of articles to be washed by a
fluid, said apparatus comprising:
a. a housing, one end of said housing having a pattern of apertures
extending therethrough, said end being adapted to engage said
matrix of articles,
b. a chamber within said housing and adapted to communicate with
said matrix of articles through said pattern of apertures,
c. conduit means communicating between said chamber and a source of
vacuum to hold said matrix of articles in contact with the
apertured end of said housing or selectively communicating between
said chamber and a source of fluid to wash said matrix of articles
through said pattern of apertures.
2. Apparatus as in claim 1, said apertures being smaller than said
articles.
3. Apparatus as in claim 1, further comprising:
d. fastening means on said housing adapted to hold said matrix of
articles in contact with the apertured end of said housing when
said conduit means has been disconnected from said source of
vacuum.
4. Apparatus for holding a matrix of articles to be washed by a
fluid, said apparatus comprising:
a. a housing having a first end and a second end,
b. a first transparent plate mounted to the first end of said
housing,
c. a second light-pervious plate mounted to the second end of said
housing, said second plate having a pattern of apertures extending
completely therethrough and adapted to correspond with said matrix
of articles, said second plate being adapted to engage said matrix
of articles,
d. a chamber within said housing between said first and second
plates and adapted to communicate with said matrix of articles
through said pattern of apertures,
e. conduit means communicating between said chamber and a source of
vacuum to hold said matrix of articles in contact with said second
plate or selectively communicating between said chamber and a
source of fluid to wash said matrix of articles through said
pattern of apertures,
f. said first transparent plate and said second light-pervious
plate providing an optical path adapted to permit visual comparison
of the relative positions of the matrix of articles and the pattern
of apertures.
5. Apparatus as in claim 4, said apertures being smaller than said
articles.
6. Apparatus as in claim 4, further comprising:
g. fastening means on said housing adapted to hold said matrix of
articles in contact with said second plate when said conduit means
has been disconnected from said source of vacuum.
7. Apparatus for holding a planar matrix of beam lead devices to be
washed by a fluid, each of said beam lead devices having a
plurality of beam leads extending beyond the perimeter thereof,
said apparatus comprising:
a. a block,
b. a pattern of mesas extending from one face of said block, the
tops of said mesas lying in one common plane, the pattern of mesas
being adapted to register with and support the matrix of beam lead
devices,
c. a pattern of channels among said mesas and adapted to underly
said beam leads when said matrix of beam lead devices is registered
with and supported by said pattern of mesas,
d. said pattern of channels providing passageways for fluid to wash
said beam lead devices,
e. a plurality of apertures extending through said block to the
faces of said mesas,
f. means to apply a vacuum to said apertures to hold said matrix of
beam lead devices to the faces of said mesas.
8. Apparatus as in claim 7, further comprising:
g. said block and mesas being formed from magnetic material,
h. a magnetic grid adapted to be attracted by said magnetic block
and mesas, said magnetic grid being adapted to register with said
pattern of channels and overly said beam leads extending over said
pattern of channels.
9. Apparatus for holding a planar matrix of beam lead devices to be
washed by a fluid, each of said beam lead devices having a
plurality of beam leads extending beyond the perimeter thereof,
said apparatus comprising:
a. a block,
b. a pattern of mesas extending from one face of said block, the
tops of said mesas lying in one common plane, the pattern of mesas
being adapted to register with and support the matrix of beam lead
devices,
c. said block and mesas being formed from magnetic material,
d. a pattern of channels among said mesas and adapted to underly
said beam leads when said matrix of beam lead devices is registered
with and supported by said pattern of mesas,
e. said pattern of channels providing passageways for fluid to wash
said beam lead devices,
f. a magnetic grid adapted to be attracted by said magnetic block
and mesas, said magnetic grid being adapted to register with said
pattern of channels and overly said beam leads extending over said
pattern of channels.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
Broadly speaking, this invention relates to apparatus for handling
an array or matrix of miniature articles. More specifically, this
invention relates to apparatus for handling an array or matrix of
closely spaced microminiature electrical devices in fixed
predetermined orientation.
2. Description of the Prior Art
In many manufacturing operations, it is necessary to handle groups
of individual workpieces. Often, such workpieces are miniature, or
even microminiature, in size and are produced in a compact array or
matrix.
One such operation involves the manufacture of microminiature beam
lead electrical devices. These beam lead devices may be
manufactured in a compact array or matrix from a particulated
semiconductor wafer having cantilevered beam leads extending
outwardly from doped regions in the semiconductor wafer. The beam
lead devices may, for example, have dimensions ranging down to
approximately 0.017 inches on a side. It would be a distinct
advantage to handle these microminiature beam lead devices in large
batches (e.g., as they exist in the matrix) for as long as possible
in the manufacturing operation, due to their small size and also to
minimize individual handling which could contaminate, break or
otherwise render useless these devices.
Moreover, it is very desirable to maintain the individual beam lead
devices of the array or matrix fixed in a predetermined orientation
relative to each other. Firstly, beam lead devices originating from
adjacent portions of the parent semiconductor wafer will have
nearly identical electrical characteristics and, where "matching"
circuits are to be fabricated, the desirability of utilizing nearly
identical beam lead devices in these "matching" circuits is
apparent. Consequently, there is an advantage in maintaining the
originally adjacent beam lead devices in the same relative
positions during the various manufacturing operations.
Parenthetically, the maintenance of this relative orientation
throughout the manufacturing process permits continuous monitoring
of the positions of those beam lead devices which have failed
electrical tests. Secondly, inasmuch as the leads of the beam lead
devices may be ultimately bonded to a patterned array of thin film
contact areas on a ceramic wafer or substrate for eventual use in
electrical circuits, these leads should be maintained in a
predetermined orientation relative to the thin film contact area
arrays until the mutual bonding is effected. In the event that this
orientation is lost, the beam lead devices must be handled
individually and optically oriented under a microscope before
bonding to the thin film contact area array.
It is clear from the foregoing that the efficient handling in the
manner described of microminiature electrical devices, particularly
of the beam lead type, is quite a difficult problem which simply
has not been solved by the prior art. The present invention
provides an eminently satisfactory solution to this problem.
SUMMARY OF THE INVENTION
One of the objects of this invention is to provide improved
apparatus for handling an array or matrix of miniature
articles.
Another of the objects of this invention is to provide improved
apparatus for handling an array or matrix of closely spaced
mircominiature electrical devices in fixed predetermined
orientation.
Other and further objects of this invention will become apparent
during the course of the following description and by reference to
the accompanying drawings and appended claims.
Briefly, and with particular reference to the handling of a matrix
of microminiature beam lead devices formed from a semiconductor
slice and mounted to a plate by means of a soluble adhesive, we
have discovered that the foregoing objects may be attained by
placing a grid over the matrix whereby the beam leads are
sandwiched between the grid and the plate and are thus captured,
drawing the grid-matrix-plate assembly onto a first chuck which
will maintain the orientation of the several beam lead devices of
the matrix during subsequent solution of the soluble adhesive,
removing the plate from the grid-matrix-plate assembly after
solution of the soluble adhesive, transferring the grid-matrix
assembly from the first chuck to a second chuck, and removing the
grid while the second chuck maintains the orientation of the
several beam lead devices of the matrix. Afterwards, the matrix may
be expanded. We have also discovered that the foregoing objects may
further be attained by providing improved chuck construction as
hereinafter disclosed.
BRIEF DESCRIPTION OF THE DRAWINGS
Referring now to the drawings, in which like numerals represent
like parts in the several views:
FIG. 1 represents a flow diagram of various principal steps in the
method of the invention, the first two steps which are
representative of certain conventional practices being included to
provide the present invention in a readily understandable frame of
reference;
FIG. 2 represents diagrammatically a partial view in elevation
showing a semiconductor slice or wafer, prepared in an appropriate
and conventional manner with a plurality of sets of interlaced beam
leads adhered to a plate by means of a soluble adhesive, the
individual beam lead devices subsequently to be prepared from the
semiconductor slice being indicated by phantom lines;
FIG. 3 represents diagrammatically a partial view in elevation
generally similar to FIG. 2 and shows the matrix of individual beam
lead devices formed after particulation in a conventional manner of
the parent semiconductor slice or wafer;
FIG. 4 represents diagrammatically a partial view in plan showing
the matrix of individual beam lead devices formed after
particulation of the parent semiconductor slice or wafer;
FIG. 5 represents diagrammatically a partial view in plan showing
the grid in position over the matrix of beam lead devices;
FIG. 6 represents a vertical view partially in section, showing the
grid-matrix-plate assembly drawn onto a first chuck, the view of
the first chuck being partially broken away to show certain details
of construction, further showing two of several spring clips
holding the grid-matrix-plate assembly to the first chuck during
one phase of the operation;
FIG. 7 represents a partial view in plan, as seen from the line
7--7 of FIG. 6, showing the offset of the perforations in the
bottom of the first chuck relative to the matrix of beam lead
devices;
FIG. 8 represents a view similar to FIG. 7 showing on a larger
scale one of the perforations in the bottom of the first chuck
offset with respect to one of the beam lead devices of the
matrix;
FIG. 9 represents a vertical diagrammatic view, partially in
section, of the second chuck receiving the grid-matrix assembly
from the first chuck;
FIG. 10 represents a partial view in elevation showing one
embodiment of second chuck holding the matrix of beam lead devices,
the first chuck and grid having been removed, and the matrix of
individual beam lead devices now ready for expansion;
FIG. 11 represents an enlarged perspective view of a variation of
the embodiment of second chuck shown in FIG. 10, partially broken
away to show certain details in construction.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Semiconductor slice or wafer 1 which, by known techniques such as
diffusion or doping, has been provided with a grid-like pattern of
electrically pertinent areas and which also by known techniques has
been provided with a plurality of sets of interlaced beam leads 2,
each set of beam leads 2 being associated with one of the
electrically pertinent areas, is conventionally cemented to plate 3
by means of a soluble adhesive 4, as shown in FIG. 2. A composition
which has been found to function satisfactorily as an adhesive, for
the purposes of this invention, is a hydrocarbon product sold under
the trademark "Biwax" (Biwax Corporation, Des Plaines, Illinois),
and a suitable solvent for this composition has been found to be
trichlorethylene. The film of adhesive 4 is shown only
diagrammatically in the drawings, it being understood that beam
leads 2 are usually fully embedded in the adhesive 4, the said
adhesive 4 contacting the bottom of semiconductor slice 1.
Semiconductor slice or wafer 1 is then particulated or subdivided
by suitable conventional means and methods such as chemical etching
to produce a matrix 5 of individual beam lead devices 6 cemented to
plate 3 through the soluble adhesive 4, the individual beam lead
devices 6 being separated from each other by channels 7 as shown in
FIGS. 3 and 4. It will be apparent that the relative orientation of
beam lead devices 6 remain the same, after particulation, as their
originating electrically pertinent areas of the parent
semiconductor slice 1. Particulation of semiconductor slice 1 may,
if desired, extend to particulation of the film or layer of soluble
adhesive 4.
Thus far has been described, very generally, operations which are
known and practiced in the art, whereby a matrix of individual beam
lead devices are produced from a semiconductor slice mounted to a
plate by means of a soluble adhesive. The matrix of cemented beam
lead devices is, at this point, ready for the application of the
method of the present invention.
Grid 8, designed to register with channels 7, is positioned over
matrix 5 and inserted into the said channels 7 to sandwich or
capture the interlaced beam leads 2 between the grid 8 and the
plate 3, as shown in FIG. 5. The height of grid 8 should be such as
not to project above the tops of beam lead devices 6 when fully
seated in channels 7. The grid 8, matrix 5 of beam lead devices 6
and plate 3, when brought into juxtaposition as just described, may
for convenience be termed the grid-matrix-plate assembly 9.
Grid-matrix-plate assembly 9 is now drawn onto a first chuck 10, as
shown in FIG. 6. First chuck 10 comprises cylindrical housing 11
having chamber 12 therein, a peripheral flange 13 at one end of the
housing 11, light-pervious (i.e., transparent or translucent) plate
14 of suitable material mounted to that end of housing 11 adjacent
flange 13, and a transparent plate 15 of suitable material mounted
to the opposite end of housing 11. Plate 14 is provided with a grid
of apertures 16 extending therethrough having the same spacing as
the beam lead devices 6 in matrix 5. Apertures 16 are slightly
smaller than the beam lead devices 6, as shown in FIG. 7. Housing
11 is further provided with a valved conduit 17 adapted to
communicate with a source of vacuum (not shown), and with a valved
conduit 18 for a purpose hereinafter to be described.
In drawing the grid-matrix-plate assembly 9 onto the first chuck
10, the assembly 9 is viewed through plates 14 and 15, a slight
separation between assembly 9 and plate 14 being maintained to
permit adjustment of their relative positions. Assembly 9 is thus
moved to such a position relative to apertures 16 that the said
apertures 16 are slightly offset from the beam lead devices 6 as
more particularly shown in FIG. 7, during all of which time vacuum
is applied to chamber 12 through conduit 17. When the positioning
shown in FIG. 7 has been attained, beam lead devices 6 are allowed
to contact plate 14, the vacuum in chamber 12 maintaining the
offset position shown in FIG. 7, grid 8 now being sandwiched or
interposed between beam leads 2 and plate 14. Fastening means 19,
which may, for example, constitute spring clips as shown in FIG. 6,
are spaced around first chuck 10 and the grid-matrix-plate assembly
9, engaging one side of plate 3 and flange 13 as shown, to hold the
assembly 9 securely in position in first chuck 10. Conduit 17 may
now be disconnected from the source of vacuum.
As more particularly shown in FIG. 8, small passageways 20 extend
through each aperture 16 of plate 14 bounded by beam lead devices
6, grid 8, and beam leads 2. In this manner, communication is
effected between chamber 12 and the film of soluble adhesive 4 on
plate 3 for a purpose to be described.
A solvent capable of dissolving adhesive 4 is introduced into
chamber 12 through conduit 18. Conduit 17 being closed by a valve
(not shown) and thus disconnected from the source of vacuum, the
solvent passes from chamber 12 through apertures 16 in plate 14 out
through passageways 20 into contact with adhesive 4, whereupon the
adhesive 4 is dissolved. The solvent, with dissolved adhesive 4,
may drain into a suitable receptacle (not shown). If desired, one
of the conduits 17 or 18 may be connected alternately to a source
of vacuum and to a source of solvent in which event the other of
said conduits 17 or 18 may be dispensed with.
After solution of adhesive 4, conduit 18 is closed by a valve (not
shown) thus disconnecting chamber 12 from the source of solvent,
and conduit 17 is again connected to the source of vacuum.
Fastening means 19 are now removed from the first chuck 10 and the
grid-matrix-plate assembly 9. Plate 3 is removed from contact with
beam leads 2, the vacuum in chamber 12 acting through apertures 16
against the matrix 5 of beam lead devices 6 and thereby holding
matrix 5 against first chuck 10 in the proper orientation, grid 8
remaining sandwiched or interposed between plate 14 of first chuck
10 and the beam leads 2. The grid 8 and matrix 5 in juxtaposition
may, for convenience, be termed the grid-matrix assembly 21. It may
be desirable, in this phase of operation, to tilt first chuck 10
and grid-matrix assembly 21 approximately 180.degree. from the
position shown in FIG. 6 particularly where the weight of grid 8 is
such that the vacuum in first chuck 10 cannot hold the grid-matrix
assembly 1 in the position shown in FIG. 6, or where the weight of
grid 8 when directly bearing on beam leads 2 might damage the said
beam leads 2.
As an alternative to introducing solvent into chamber 12, after
disconnecting chamber 12 from the source of vacuum, the solvent may
be applied externally to adhesive 4 simply by dipping the
grid-matrix-plate assembly 9, held as hereinbefore described to
first chuck 10 by fastening means 19, in a container of solvent.
This would eliminate the previously described operation of
relatively offsetting apertures 16 and beam lead devices 6. As a
further alternative, the vacuum source need not be disconnected
from chamber 12 and the solvent externally applied as just
described; in addition to eliminating the previously described
operation of relatively offsetting apertures 16 and beam lead
devices 6, this further alternative would eliminate the need for
fastening devices 19.
In the phase of operation above described (viz., solution of the
adhesive 4 by means of a solvent to free plate 3), beam lead
devices 6 might tend to move or float on a capillary film of
solvent between the said beam lead devices 6 and plate 14. Grid 8,
nesting in channels 7, positively prevents such motion which
otherwise might result in disorientation of the beam lead devices
6.
In any event, with the grid-matrix assembly 21 held to first chuck
10 by means of vacuum, grid 8 being interposed between beam leads 2
of matrix 5 and plate 14, the next step in the method of the
present invention is to transfer grid-matrix assembly 21 to a
second chuck 22 in such manner that beam leads 2 are interposed
between grid 8 and the second chuck 22. Thus, when the second chuck
22 has engaged and holds matrix 5, the first chuck 10 can be
disconnected from the source of vacuum and removed from the
grid-matrix assembly 21.
One embodiment of second chuck 22 comprises a block 23 of porous
material, such as foamed plastic, one side 24 of which engages beam
leads 2, the opposite side 25 thereof being subjected to a vacuum
by suitable means known to the art.
Such means may, for example, comprise open mouthed bell 26 with
flange 27 closely fitted to block 23, the said bell 26 having a
chamber 28 communicating with side 25 of block 23, and with conduit
29 communicating between chamber 28 and a source of vacuum (not
shown). The applied vacuum is exercized through the porous block 23
to hold to side 24 thereof the individual beam lead devices 6 of
the matrix 5 in fixed and known orientation.
Another embodiment of second chuck 22 comprises a magnetized block
attracting grid 8 which, in this embodiment, has been formed from
suitable magnetic material. Thus, beam leads 2 will be sandwiched
between grid 8 and the magnetized block.
Yet another embodiment of second chuck 22 comprises a porous
magnetized block (formed of such material as sintered nickel)
functioning as both embodiments of second chuck 22 hereinabove
described. Thus, the block will attract this magnetic grid 8 to
sandwich beam leads 2 between the grid 8 and the block and, also, a
vacuum applied to one side of the block will be exercized through
the porous block body to hold to the opposite side of the block the
individual beam lead devices 6 of the matrix 5.
Still other embodiments of second chuck 22 are shown in FIGS. 10
and 11 and may employ the effects of vacuum and/or magnetism to
hold the grid-matrix assembly 21. The embodiment of second chuck 22
shown in FIG. 10 comprises a magnetic block 30 having thereon a
matrix of mesas 31 in the same geometrical arrangement as the
matrix 5 of beam lead devices 6, there being a grid of channels 32
among the mesas 31. Magnetic block 30 attracts magnetic grid 8
thereby sandwiching beam leads 2 between grid 8 and the tops of
mesas 31. In the variation of embodiment shown in FIG. 11,
apertures 33 extend entirely through non-magnetic block 30 from the
rear face 34 thereof to the tops of the mesas 31; upon application
of vacuum by suitable means (such as the open-mouthed bell 26 and
conduit 28 shown in FIG. 9) to the rear face 34 of the block 30,
the matrix 5 of beam lead devices 6 will be held fast to the tops
of mesas 31. In yet another variation of embodiment, combining the
features shown in FIGS. 10 and 11, block 30 is both magnetic, thus
attracting magnetic grid 8, and has apertures 33 for the
application of vacuum to the beam lead devices 6 as hereinabove
described, whereby the matrix 5 is held fast in proper
orientation.
With the matrix 5 held on any of the embodiments of second chuck 22
hereinabove described, further additions of solvent may be applied
to remove all traces of adhesive 4 which may remain on beam leads
2. A particular advantage of the embodiments of second chuck 22
shown in FIGS. 10 and 11 resides in the presence of channels 32.
The interlaced beam leads 2 of the beam lead devices 6 extend over
channels 32. Solvent, forced through the channels 32, will more
efficiently remove the remaining traces of adhesive 4 from the beam
leads 2. The beam lead devices 6 may then, if desired, be washed
and dried.
Grid 8 may now be lifted out of channels 7 in matrix 5.
Matrix 5 may then be expanded (i.e., the beam leads 2 of adjacent
beam lead devices 6 are removed from interlaced relationship)
thereby to permit the individual beam lead devices 6 to easily be
separated from the matrix 5 for further processing in the
manufacturing operation.
It will be apparent, from all of the foregoing, that the apparatus
of the present invention maintains all of the beam lead devices 6
in known and constant orientation from the particulation of
semiconductor slice 1 up to and including the expansion of matrix
5.
* * * * *