Method for securing electronic components to a substrate

• US 8,662,377 B2
• Filed: 04/22/2005
• Issued: 03/04/2014
• Est. Priority Date: 04/22/2004
• Status: Active Grant

• Current Assignee: Semikron Elektronik GmbH & Company KG (Heilbronner Holding GbR)
• Original Assignee: Semikron Elektronik GmbH & Company KG (Heilbronner Holding GbR)
• Inventors: Palm, Gerhard
• Primary Examiner(s): Ewald, Maria Veronica
• Assistant Examiner(s): MEHTA, MEGHA S
• Application Number:
  US11/112,803
• Publication Number:
  US 20050247760A1
• Time in Patent Office: 3,238 Days
• Field of Search: 228/193, 228/178, 228/179.1, 228/190, 228/199, 228/225, 228/245, 228/249, 156 8911- 8928, 156/230, 156/235, 156/238, 156/241
• US Class Current: 228/253
• CPC Class Codes: B22F 2998/00 Supplementary information concerning processes or compositions relating to powder metallurgy
• CPC Class Codes: B22F 7/064 using an intermediate powder layer
• CPC Class Codes: B23K 35/025 Pastes, creams, slurries
• CPC Class Codes: B23K 35/3006 Ag as the principal constituent
• CPC Class Codes: H01L 21/6835 using temporarily an auxiliary support
• CPC Class Codes: H01L 2221/68354 used to support diced chips prior to mounting
• CPC Class Codes: H01L 2221/68363 used in a transfer process involving transfer directly from an origin substrate to a target substrate without use of an intermediate handle substrate
• CPC Class Codes: H01L 2224/29339 Silver [Ag] as principal constituent
• CPC Class Codes: H01L 2224/32225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/37099 Material
• CPC Class Codes: H01L 2224/83005 being a temporary or sacrificial substrate
• CPC Class Codes: H01L 2224/83191 wherein the layer connectors are disposed only on the semiconductor or solid-state body
• CPC Class Codes: H01L 2224/83201 Compression bonding
• CPC Class Codes: H01L 2224/83801 Soldering or alloying
• CPC Class Codes: H01L 2224/8384 Sintering
• CPC Class Codes: H01L 2224/97 the devices being connected to a common substrate, e.g. interposer, said common substrate being separable into individual assemblies after connecting
• CPC Class Codes: H01L 24/27 Manufacturing methods
• CPC Class Codes: H01L 24/29 of an individual layer connector
• CPC Class Codes: H01L 24/33 of a plurality of layer connectors
• CPC Class Codes: H01L 24/36 Structure, shape, material or disposition of the strap connectors prior to the connecting process
• CPC Class Codes: H01L 24/40 : of an individual strap connector
• CPC Class Codes: H01L 24/83 : using a layer connector
• 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 2924/00014 : the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/01005 : Boron [B]
• CPC Class Codes: H01L 2924/01006 : Carbon [C]
• CPC Class Codes: H01L 2924/01033 : Arsenic [As]
• CPC Class Codes: H01L 2924/01047 : Silver [Ag]
• CPC Class Codes: H01L 2924/01068 : Erbium [Er]
• CPC Class Codes: H01L 2924/01322 : Eutectic Alloys, i.e. obtained by a liquid transforming into two solid phases
• CPC Class Codes: H01L 2924/1301 : Thyristor
• CPC Class Codes: H01L 2924/19043 : being a resistor
• CPC Class Codes: H05K 2201/10984 : Component carrying a connection agent, e.g. solder, adhesive
• CPC Class Codes: H05K 2203/0156 : Temporary polymeric carrier or foil, e.g. for processing or transferring
• CPC Class Codes: H05K 2203/0278 : Flat pressure, e.g. for connecting terminals with anisotropic conductive adhesive
• CPC Class Codes: H05K 2203/0338 : Transferring metal or conductive material other than a circuit pattern, e.g. bump, solder, printed component
• CPC Class Codes: H05K 2203/1131 : Sintering, i.e. fusing of metal particles to achieve or improve electrical conductivity
• CPC Class Codes: H05K 3/321 : by conductive adhesives

Abstract

A method for securing electronic components, in particular power semiconductor components such as diodes, transistors or thyristors, and connection elements, to a substrate by pressure sintering. The method includes: applying a pastelike layer, made up of a metal powder and a solvent, to a supporting film; drying the pastelike layer; applying at least one component to the dried layer; subjecting the at least one component, the supporting film and the dried layer to pressure, as a result of which the adhesive force between the layer and the component becomes greater than that between the layer and the supporting film; lifting off the at least one component, with the layer adhering to it, from the supporting film; positioning the component, with the layer adhering to it, to the substrate; and subjecting the substrate and the component to pressure, for connecting them by sintering.

Claims

1. A method for securing a first an electronic structure to an electronic supporting structure by pressure sintering, the method comprising:

a) applying a pastelike layer, comprising a metal powder and a solvent, directly to a first, structured supporting film;

b) disposing the electronic structure on said pastelike layer;

c) drying said pastelike layer, thereby forming metal chips, on said first, structured supporting film;

d) applying a second film, thinner than said first, structured supporting film, to said electronic structure on a side thereof which is opposed to said dried pastelike layer;

e) subjecting said first, structured supporting film, said dried pastelike layer, the electronic structure and said second film to pressure, whereby the adhesive force between said dried pastelike layer and the electronic structure becomes greater than the adhesive force between said dried pastelike layer and said first, structured supporting film and causes said metal chips of said dried pastelike layer to adhere at least partly to the electronic structure;

f) removing said second film, and the electronic structure with said dried pastelike layer adhering thereto, from said first, structured supporting film;

g) applying at least one of the electronic supporting structure and a conductor track to said dried, pastelike layer adhered to the first electronic structure;

h) removing said second film from the electronic structure; and

i) subjecting said at least one of said conductor track and the electronic supporting structure with the electronic structure and metal chips of said dried pastelike layer disposed therebetween, to pressure, for mutually connecting them by sintering.

2. The method of claim 1, wherein said electronic structure is an electronic component, and said electronic supporting structure is a substrate.

3. The method of claim 1, wherein said electronic structure is a connection element and said electronic supporting structure is one of an electronic component and a substrate.

4. The method of claim 1, wherein said supporting film comprises a polyester film having a thickness of between approximately 100 μ

m and approximately 200 μ

m.

5. The method of claim 1, wherein said second film is structured to coat said electronic structure in structured form.

6. The method of claim 1, wherein said dried pastelike layer comprises a mixture of silver powder with cyclohexanol in a ratio by volume of from approximately 1:

2 to approximately 1;

4, and having a thickness of between approximately 10 μ

m and approximately 50 μ

m.

7. The method of claim 1, wherein said dried pastelike layer is dried at a temperature of between approximately 100°

C. and approximately 200°

C.

8. The method of claim 1, wherein said second film includes a polyester film having a thickness of between approximately 10 μ

m and approximately 100 μ

m.

9. The method of claim 1, wherein said first, structured supporting film, said dried pastelike layer and said second film having the electronic structure carried thereon are subjected to a pressure of between approximately 20 MPa and approximately 80 MPa for from about 5 seconds to about 20 seconds.

10. The method of claim 9, wherein said first, structured supporting film, said dried pastelike layer and said second film having the electronic structure carried thereon are subjected to a temperature of between approximately 40°

C. and approximately 100°

C. for a period of from about 5 seconds to about 20 seconds.

11. The method of claim 1, wherein said metal powder is silver or silver alloy.

12. The method of claim 4, wherein said second film includes a polyester film having a thickness of between approximately 10 μ

m and approximately 100 μ

m.