Methods for creating elements of predetermined shape and apparatus using these elements

• US 6,586,338 B2
• Filed: 04/23/2002
• Issued: 07/01/2003
• Est. Priority Date: 11/02/1999
• Status: Expired due to Term

• Current Assignee: RUIZHANG TECHNOLOGY LIMITED COMPANY
• Original Assignee: Alien Technology Corporation
• Inventors: Smith, John Stephen, Hadley, Mark A., Tu, Jay
• Primary Examiner(s): Cuneo, Kamand
• Assistant Examiner(s): KILDAY, LISA A
• Application Number:
  US10/131,541
• Publication Number:
  US 20020127864A1
• Time in Patent Office: 434 Days
• Field of Search: 438/406, 438/455, 438/665, 438/666, 438/693, 438/706, 438/733, 438/745, 438/756, 438/692
• US Class Current: 438/692
• CPC Class Codes: H01L 21/6836 Wafer tapes, e.g. grinding or dicing support tapes adhesive tapes in general C09J7/20
• CPC Class Codes: H01L 21/78 with subsequent division of the substrate into plural individual devices cutting to change the surface-physical characteristics or shape of semiconductor bodies H01L21/304
• CPC Class Codes: H01L 21/7806 involving the separation of the active layers from a substrate
• CPC Class Codes: H01L 2221/68327 used during dicing or grinding
• CPC Class Codes: H01L 2221/6834 used to protect an active side of a device or wafer
• CPC Class Codes: H01L 2224/24227 the HDI interconnect not connecting to the same level of the item at which the semiconductor or solid-state body is mounted, e.g. the semiconductor or solid-state body being mounted in a cavity or on a protrusion of the item
• CPC Class Codes: H01L 2224/95085 being a liquid, e.g. for fluidic self-assembly
• CPC Class Codes: H01L 2224/95136 involving guiding structures, e.g. shape matching, spacers or supporting members
• 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 27/156 two-dimensional arrays
• 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 2924/01011 Sodium [Na]
• CPC Class Codes: H01L 2924/01013 Aluminum [Al]
• CPC Class Codes: H01L 2924/01015 Phosphorus [P]
• CPC Class Codes: H01L 2924/01019 Potassium [K]
• CPC Class Codes: H01L 2924/01021 Scandium [Sc]
• CPC Class Codes: H01L 2924/01027 : Cobalt [Co]
• CPC Class Codes: H01L 2924/01033 : Arsenic [As]
• CPC Class Codes: H01L 2924/01072 : Hafnium [Hf]
• CPC Class Codes: H01L 2924/01074 : Tungsten [W]
• CPC Class Codes: H01L 2924/01082 : Lead [Pb]
• CPC Class Codes: H01L 2924/10253 : Silicon [Si]
• CPC Class Codes: H01L 2924/12041 : LED
• CPC Class Codes: H01L 2924/12043 : Photo diode
• CPC Class Codes: H01L 2924/14 : Integrated circuits
• CPC Class Codes: H01L 2924/15153 : the die mounting substrate comprising a recess for hosting the device
• CPC Class Codes: H01L 2924/15155 : the shape of the recess being other than a cuboid
• CPC Class Codes: H01L 2924/15157 : Top view
• CPC Class Codes: H01L 2924/15165 : Monolayer substrate
• CPC Class Codes: H01L 2924/15788 : Glasses, e.g. amorphous oxides, nitrides or fluorides

Abstract

Methods for forming elements having a predetermined shape and for assembling the elements. In one example of a method, each of the elements includes a functional component which is disposed on a first face of a first substrate. A layer representing a first portion of the first substrate at a second face of the first substrate is removed, leaving a second portion of the first substrate on the first substrate. The second portion is etched through a first patterned mask on a surface of the second portion. The plurality of elements is then released from the first substrate. The plurality of elements may then be combined with a fluid to form a slurry. In another example of a method, the first face is etched vertically in regions adjacent to the edges of the plurality of elements, and regions below the first face are etched laterally, and then the plurality of elements are released from the substrate. Other methods of creating elements having a predetermined shape are described, and methods of using and/or assembling these elements are also described.

Claims

1. A method for creating elements having a predetermined shape, said method comprising:

fabricating in a first substrate a plurality of a component having at least one of electrical, chemical, or an electro-mechanical element in a plurality of elements, said components being disposed on a first face of said first substrate, said first substrate having two surfaces comprising said first face and a second face;

removing a layer representing a first portion of said first substrate at said second face leaving a second portion of said first substrate on said first substrate;

etching said second portion of said first substrate through a first patterned mask on a surface of said second portion;

releasing said plurality of elements from said first substrate; and

combining said plurality of elements with a fluid to form a slurry.

2. A method for creating elements having a predetermined shape, said method comprising:

fabricating in a first substrate a plurality of a component having at least one of electrical, chemical, or an electron-mechanical element in a plurality of elements, said components being disposed on a first face of said first substrate, said first substrate having two surfaces comprising said first face and a second face;

removing a layer representing a first portion of said first substrate at said second face leaving a second portion of said first substrate on said first substrate;

etching said second portion of said first substrate through a first patterned mask on a surface of said second portion;

releasing said plurality of elements from said first substrate;

bonding said first face of said first substrate to a second substrate; and

wherein said removing said layer comprises a mechanical process of one of grinding, lapping or polishing said first portion and wherein said method further comprises;

combining said plurality of elements with fluid to form a slurry.

3. A method for creating elements having a predetermined shape, said method comprising:

fabricating in a first substrate a plurality of a component having at least one of electrical, chemical, or an electro-mechanical element in a plurality of elements, said components being disposed on a first face of said first substrate, said first substrate having two surfaces comprising said first face and a second face;

removing a layer representing a first portion of said first substrate at said second face leaving a second portion of said first substrate on said first substrate;

etching said second portion of said first substrate through a first patterned mask on a surface of said second portion;

releasing said plurality of elements from said first substrate;

bonding said first face of said first substrate to a second substrate; and

wherein said first patterned mask is formed by aligning on said second face a plurality of shapes formed by said first patterned mask relative to functional components disposed on said first face and wherein said etching said second portion comprises first etching with an isotropic etchant and second etching with an anisotropic etchant, and wherein said method further comprises;

combining said plurality of elements with a fluid to form a slurry.

4. A method for creating elements having a predetermined shape, said method comprising:

fabricating in a first substrate a plurality of a component having at least one of electrical, chemical, or an electro-mechanical element in a plurality of elements, said components being disposed on a first face of said first substrate, said first substrate having two surfaces comprising said first face and a second face;

removing a layer representing a first portion of said first substrate at said second face leaving a second portion of said first substrate on said first face;

etching said second portion of said first substrate through a first patterned mask on a surface of said second portion;

releasing said plurality of elements from said first substrate;

bonding said first face of said first substrate to a second substrate; and

wherein said etching said second portion exposes at least a portion of each of said plurality of elements and wherein each of said plurality elements comprises at least one functional component which comprises an electrical component; and

wherein each of said elements has a substantially quadrilateral cross section which is said predetermined shape which is designed to fit into an opening on a receiving substrate, and wherein each of said elements comprises a pixel driver and wherein said method further comprises;

combining said plurality of elements with a fluid to form a slurry.

5. A method for creating elements having a predetermined shape, said method comprising:

fabricating in a first substrate a plurality of a component having at least one of electrical, chemical, or electro-mechanical element in a plurality of elements, said components being disposed on a first face of said first substrate, said first substrate having two surfaces comprising said first face and a second face;

applying, after said fabricating, a release layer on said first face;

etching said second face to expose at least a portion of each of said plurality of elements;

etching said release layer; and

wherein said etching said release layer releases said plurality of elements and wherein said method further comprises;

combining said plurality of elements with a fluid to form a slurry after releasing said plurality of elements.

6. A method as in claim 5 wherein said etching said second face is performed through a first patterned mask which is formed by aligning on said second face a plurality of shapes formed by said first patterned mask relative to said functional components disposed on said first face.

7. A method as in claim 6 wherein each of said elements has a substantially quadrilateral cross section which is said predetermined shape which is designed to fit into an opening on a receiving substrate and wherein each of said plurality of elements comprises at least one component which comprises an electrical component.

8. A method as in claim 7 wherein each of said function components is a pixel driver.

9. A method as in claim 7 wherein said first face comprises a passivation layer and wherein said release layer is deposited over said passivation layer to completely cover said passivation layer and wherein said release layer comprises at least one of tungsten and titanium tungsten.

10. A method for creating elements having a predetermined shape, said method comprising:

fabricating in a first substrate a plurality of a component having at least one of electrical, chemical, or an electron-mechanical element in a plurality of elements, said plurality of components being disposed on a first face of said substrate which also has a second face;

etching vertically, in a first etching process, regions of said first face which are adjacent to edges of said plurality of elements;

etching laterally, in a second etching process, regions below said first face which are adjacent to said edges;

releasing said plurality of elements from said first substrate; and

combining said plurality of elements with a fluid to form a slurry.

11. A method as in claim 10 wherein each of said elements has a substantially quadrilateral cross section which is said predetermined shape which is designed to fit into an opening on a receiving substrate.

12. A method as in claim 11 wherein each of said components comprises an electrical component for at least one of (a) a liquid crystal display pixel;

(b) a light emitting diode display pixel;

(c) a solar cell element; and

(d) an electromagnetic signal detector.

13. A method for creating elements having a predetermined shape, said method comprising:

depositing a first layer into a second layer;

fabricating a plurality of a component having at least one of electrical, chemical, or an electro-mechanical element in a plurality of elements in said first layer;

etching at least said first layer to determine said predetermined shape for each of said plurality of elements;

etching said second layer such that a density of said second layer, after said etching of said second layer, is reduced;

releasing said plurality of elements from said second layer after said etching of said second layer, wherein a thickness of said first layer is related to a depth of each of said plurality of elements; and

combining said plurality of elements with a fluid to form a slurry.

14. A method as in claim 13 wherein each of said elements has a substantially quadrilateral cross section which is said predetermined shape which is designed to fit into an opening on a receiving substrate.

15. A method as in claim 14 wherein each of said components comprises an electrical component for at least one of (a) a liquid crystal display pixel;

(b) a light emitting diode display pixel;

(c) a solar cell element; and

(d) an electromagnetic signal detector.

16. A method of assembling a structure on a receiving substrate, said method comprising:

dispensing a slurry over said receiving substrate having a plurality of openings, said slurry comprising a fluid and a plurality of shaped elements, wherein at least one of said shaped elements becomes disposed into one of said openings, and wherein said plurality of shaped elements were created by a method comprising;

fabricating in a first substrate a plurality of a component having at least one of electrical, chemical, or an electro-mechanical element in a plurality of elements, said components being disposed on a first face of said first substrate, said first substrate having two surfaces comprising said first face and a second face;

removing a layer representing a first portion of said first substrate at said second face leaving a second portion of said first substrate on said first substrate;

etching said second portion of said first substrate through a first patterned mask on a surface of said second portion;

releasing said plurality of elements from said first substrate;

washing said receiving substrate after said dispensing.

17. A method as in claim 16 wherein said washing removes any shaped elements which are not disposed in one of said openings.

18. A method as in claim 17 further comprising:

planarizing said receiving substrate after said washing;

interconnecting electrically at least a portion of said shaped elements disposed in said openings.