Method and apparatus for the assembly of microfabricated devices

• US 5,355,577 A
• Filed: 06/23/1992
• Issued: 10/18/1994
• Est. Priority Date: 06/23/1992
• Status: Expired due to Fees

• Current Assignee: Cohn, Michael B.
• Original Assignee: Cohn, Michael B.
• Inventors: Cohn, Michael B.
• Primary Examiner(s): ECHOLS, PERCY W
• Application Number:
  US07/902,986
• Time in Patent Office: 847 Days
• Field of Search: 29/DIG. 46, 29/743, 29/744, 29/592.1, 29/832, 29/729
• US Class Current: 29/592.1
• CPC Class Codes: B81C 2203/054 using structural alignment aids, e.g. spacers, interposers, male/female parts, rods or balls
• CPC Class Codes: B81C 2203/058 Aligning components using methods not provided for in B81C2203/051 - B81C2203/052
• CPC Class Codes: B81C 3/005 Passive alignment, i.e. without a detection of the position of the elements or using only structural arrangements or thermodynamic forces
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: H01L 2224/24051 Conformal with the semiconductor or solid-state device
• CPC Class Codes: H01L 2224/24226 the HDI interconnect connecting to the same level of the item at which the semiconductor or solid-state body is mounted, e.g. the item being planar
• CPC Class Codes: H01L 2224/95085 being a liquid, e.g. for fluidic self-assembly
• CPC Class Codes: H01L 2224/95122 by applying vibration
• CPC Class Codes: H01L 2224/95136 involving guiding structures, e.g. shape matching, spacers or supporting members
• CPC Class Codes: H01L 2224/95144 Magnetic alignment, i.e. using permanent magnetic parts in the semiconductor or solid-state body
• CPC Class Codes: H01L 2224/95145 Electrostatic alignment, i.e. polarity alignment with Coulomb charges
• CPC Class Codes: H01L 24/24 of an individual high density interconnect connector
• CPC Class Codes: H01L 24/82 by forming build-up interconnects at chip-level, e.g. for high density interconnects [HDI] interconnection structure between a plurality of semiconductor chips H01L23/5389
• CPC Class Codes: H01L 24/95 at chip-level, i.e. with connecting carried out on a plurality of singulated devices, i.e. on diced chips
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/01005 Boron [B]
• CPC Class Codes: H01L 2924/01006 Carbon [C]
• CPC Class Codes: H01L 2924/01013 Aluminum [Al]
• CPC Class Codes: H01L 2924/01014 Silicon [Si]
• CPC Class Codes: H01L 2924/0102 Calcium [Ca]
• CPC Class Codes: H01L 2924/01023 : Vanadium [V]
• CPC Class Codes: H01L 2924/01029 : Copper [Cu]
• CPC Class Codes: H01L 2924/01033 : Arsenic [As]
• CPC Class Codes: H01L 2924/01074 : Tungsten [W]
• CPC Class Codes: H01L 2924/01075 : Rhenium [Re]
• CPC Class Codes: H01L 2924/014 : Solder alloys
• CPC Class Codes: H01L 2924/10329 : Gallium arsenide [GaAs]
• CPC Class Codes: H01L 2924/12041 : LED
• CPC Class Codes: H01L 2924/12042 : LASER
• CPC Class Codes: H01L 2924/1306 : Field-effect transistor [FET]
• CPC Class Codes: H01L 2924/14 : Integrated circuits
• CPC Class Codes: H01L 2924/19041 : being a capacitor
• CPC Class Codes: H01L 2924/19043 : being a resistor
• CPC Class Codes: H01L 2924/30105 : Capacitance
• CPC Class Codes: H02K 99/00 : Subject matter not provided for in other groups of this subclass
• CPC Class Codes: H05K 13/028 : Simultaneously loading a plurality of loose objects, e.g. by means of vibrations, pressure differences, magnetic fields
• CPC Class Codes: H05K 13/0482 : using templates; using magazines, the configuration of which corresponds to the sites on the boards where the components have to be attached
• CPC Class Codes: Y10S 29/046 : Vibration
• CPC Class Codes: Y10T 29/49002 : Electrical device making
• CPC Class Codes: Y10T 29/4913 : Assembling to base an electrical component, e.g., capacitor, etc.
• CPC Class Codes: Y10T 29/5313 : Means to assemble electrical device
• CPC Class Codes: Y10T 29/53196 : Means to apply magnetic force directly to position or hold work part

Abstract

Abstract: A method of rapidly assembling many discrete microelectronic or micro-mechanical devices 56 (FIG. 2 ) in a precise configuration (FIG. 8f). The devices are placed randomly on a template (FIG. 3 ) consisting of a pair of oppositely charged planar electrodes. The upper electrode contains a multiplicity of apertures. The template is vibrated and the devices are attracted to the apertures and trapped thereat. The shape of a given aperture determines the number, orientation, and type of device that it traps. The process is completed by mechanically and electrically connecting the devices. The present method for serf-assembly allows many sub-millimeter sized electronic components or other particles to be rapidly assembled into a predetermined configuration. The method relies on vibration and weak electrical or magnetic forces.

Claims

1. Apparatus for arranging microfabricated devices in a predetermined planar pattern, comprising:

(a) a cell or container for containing said microfabricated particles;

(b) vibration means for rapidly agitating the particles within the container;

(c) a template comprising

(1) a first planar electrode overlying an inner surface of said container;

(2) a second, parallel planar electrode substantially covering said first electrode, and having a plurality of apertures; and

(d) a voltage source applied between the electrodes,

whereby the voltage causes electric flux to emanate from each aperture, thus attracting and binding any particle which may randomly approach an aperture under influence of the vibration, allowing rapid assembly of the particles into substantially any desired pattern, as determined by the placement of the apertures.

2. The apparatus of claim 1, in which

(a) each particle bears a conductive pad of a shape which is asymmetric with respect to rotation and reflection, and

(b) each aperture is substantially identical in shape to said conductive pad,

whereby each particle bound to an aperture will be oriented with its conductive pad in overlying and aligned relationship to the aperture, by the principle of minimization of potential energy.

3. The apparatus of claim 1, further comprising

(a) particles of a first type, each first type of particle having a conductive pad of a predetermined shape on its surface;

(b) particles of a second type, each second type of particle having a conductive pad of a second predetermined shape on its surface, said second shape differing from said first shape,

and wherein the apertures comprise first apertures whose shapes are substantially identical to the first shape and second apertures whose shapes are substantially identical to the second shape,

whereby a voltage applied between the electrodes causes electric flux to emanate from the apertures, thus causing particles of the first type to be bound at the first apertures, and particles of the second type at the second apertures.

4. A method of fabricating an array of spaced discrete particles, comprising the steps of:

(a) providing a cell or container;

(b) providing a template comprising;

(1) a first planar electrode overlying an inner surface of said container; and

(2) a second, parallel planar electrode substantially covering said first electrode, and having a plurality of apertures;

(c) placing a plurality of the discrete particles in the container;

(d) applying a voltage source between the electrodes; and

(e) agitating the particles,

whereby the voltage causes electric flux to emanate from each aperture, thus attracting and binding any particle which may randomly approach an aperture under influence of the vibration, allowing rapid assembly of the particles into a desired planar pattern, as determined by the placement of the apertures.

5. The method of claim 4, in which

(a) each particle bears a conductive pad of a shape which is asymmetric with respect to rotation and reflection, and

(b) each aperture is substantially identical in shape to said conductive pad,

whereby each particle bound to an aperture will be oriented with its conductive pad in overlying and aligned relationship to the aperture, by the principle of minimization of potential energy.

6. The method of claim 4, further comprising

(a) particles of a first type, each first type of particle having a conductive pad of a predetermined shape on its surface;

(b) particles of a second type, each second type of particle having a conductive pad of a second predetermined shape on its surface, said second shape differing from said first shape,

and wherein the apertures comprise first apertures whose shapes are substantially identical to the first shape and second apertures whose shapes are substantially identical to the second shape,

whereby a voltage applied between the electrodes causes electric flux to emanate from the apertures, thus attracting and binding particles of the first type to the first apertures, and particles of the second type to the second apertures.