MASK-LESS FABRICATION OF VERTICAL THIN FILM BATTERIES

• US 20150325862A1
• Filed: 12/17/2013
• Published: 11/12/2015
• Est. Priority Date: 12/19/2012
• Status: Active Grant

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: SONG, Daoying, JIANG, Chong, KWAK, Byung-Sung Leo
• Granted Patent: US 9,768,450 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: C23C 14/088 of the type ABO3 with A representing alkali, alkaline earth metal or Pb and B representing a refractory or rare earth metal
• CPC Class Codes: C23C 14/34 Sputtering
• CPC Class Codes: H01M 10/0436 Small-sized flat cells or batteries for portable equipment
• CPC Class Codes: H01M 10/0585 of accumulators having only flat construction elements, i.e. flat positive electrodes, flat negative electrodes and flat separators
• CPC Class Codes: H01M 4/0426 Sputtering
• CPC Class Codes: H01M 6/40 Printed batteries , e.g. thin film batteries
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product

Abstract

A method of fabricating a thin film battery may comprise: depositing a first stack of blanket layers on a substrate, the first stack comprising a cathode current collector, a cathode, an electrolyte, an anode and an anode current collector; laser die patterning the first stack to form one or more second stacks, each second stack forming the core of a separate thin film battery; blanket depositing an encapsulation layer over the one or more second stacks; laser patterning the encapsulation layer to open up contact areas to the anode current collectors on each of the one or more second stacks; blanket depositing a metal pad layer over the encapsulation layer and the contact areas; and laser patterning the metal pad layer to electrically isolate the anode current collectors of each of the one or more thin film batteries. For electrically non-conductive substrates, cathode contact areas are opened-up through the substrate.

Claims

1. A method of fabricating a thin film battery comprising:

depositing a first stack of blanket layers on an electrically conductive substrate, said first stack comprising a cathode current collector layer, a cathode layer, an electrolyte layer, an anode layer and an anode current collector layer;

laser die patterning said first stack to form one or more second stacks, each second stack forming the core of a separate thin film battery;

blanket depositing an encapsulation layer over said one or more second stacks;

laser patterning said encapsulation layer to open up contact areas to the anode current collectors on each of said one or more second stacks;

blanket depositing a metal pad layer over said encapsulation layer and said contact areas; and

laser patterning said metal pad layer to electrically isolate said anode current collectors of each of said one or more thin film batteries.

2. The method of claim 1, further comprising, after said laser patterning said encapsulation layer and before said blanket depositing said metal pad layer, blanket depositing a second encapsulation layer and laser patterning said second encapsulation layer to open up said contact areas.

3. The method of claim 1, wherein said laser patterning said metal pad layer is laser dicing said electrically conductive substrate covered by layers including said metal pad layer to physically separate the separate TFBs.

4. The method of claim 1, wherein said anode layer is a lithium layer.

16. The method of claim 1, further comprising annealing said cathode layer.

5. A method of fabricating a thin film battery comprising:

depositing a first stack of blanket layers on the top surface of an electrically non-conductive substrate, the first stack comprising a cathode current collector layer, a cathode layer, an electrolyte layer, an anode layer and an anode current collector layer;

laser die patterning said first stack to form one or more second stacks, each second stack forming the core of a separate thin film battery;

blanket depositing an encapsulation layer over said one or more second stacks;

laser patterning said encapsulation layer to open up anode contact areas to the anode current collectors on each of said one or more second stacks;

blanket depositing a metal pad layer over said encapsulation layer and said anode contact areas;

laser patterning said metal pad layer to electrically isolate the anode current collectors of each of said one or more thin film batteries; and

opening up, through said substrate, cathode contact areas on the cathode current collector for each of said one or more thin film batteries.

6. The method of claim 5, wherein said first stack further comprises a die patterning assistance layer between said electrically non-conductive substrate and said cathode current collector layer.

7. The method of claim 5, wherein said opening up cathode contact areas includes laser ablating said substrate.

8. The method of claim 5, wherein said laser patterning said encapsulation layer further includes removing strips of said encapsulation layer completely around and adjacent to the edges of said second stacks, said strips being roughly the thickness of said encapsulation layer away from the edges of said second stacks.

9. The method of claim 5, wherein said opening up cathode contact areas includes:

depositing resist over the bottom surface of said substrate;

removing portions of said resist to expose areas of the bottom surface of said substrate; and

etching through said substrate at the exposed areas to expose said cathode contact areas.

17. The method of claim 5, further comprising annealing said cathode layer.

18. The method of claim 6, wherein said die patterning assistance layer is an amorphous silicon layer.

19. The method of claim 9, wherein said resist is photoresist.

20. The method of claim 9, wherein said etching is wet etching.

10. An apparatus for fabricating thin film batteries, comprising:

a first system for depositing a first stack of blanket layers on a substrate, said first stack comprising a cathode current collector layer, a cathode layer, an electrolyte layer, an anode layer and an anode current collector layer;

a second system for laser die patterning said first stack to form one or more second stacks, each second stack forming the core of a separate thin film battery;

a third system for blanket depositing an encapsulation layer over said one or more second stacks;

a fourth system for laser patterning said encapsulation layer to open up anode contact areas to the anode current collectors on each of said one or more second stacks;

a fifth system for blanket depositing a metal pad layer over said encapsulation layer and said anode contact areas; and

a sixth system for laser patterning said metal pad layer to electrically isolate said anode current collectors of each of said one or more thin film batteries.

11. The apparatus of claim 10, wherein said second system and said fourth system are the same system.

12. The apparatus of claim 10, wherein said substrate is an electrically non-conductive substrate, and further comprising a seventh system for opening up, through said substrate, cathode contact areas on the cathode current collector for each of said one or more thin film batteries.

13. The apparatus of claim 10, wherein said substrate is an electrically conductive substrate.

14. (canceled)

15. (canceled)