METHOD FOR FORMING A THIN-FILM LITHIUM-ION BATTERY

• US 20110076567A1
• Filed: 09/08/2010
• Published: 03/31/2011
• Est. Priority Date: 09/28/2009
• Status: Active Grant

• Current Assignee: Stmicroelectronics Tours SAS (STMicroelectronics NV)
• Original Assignee: Stmicroelectronics Tours SAS (STMicroelectronics NV)
• Inventors: Bouillon, Pierre
• Granted Patent: US 8,784,511 B2
• Time in Patent Office: Days
• US Class Current: 429/246
• CPC Class Codes: H01M 10/0436 Small-sized flat cells or batteries for portable equipment
• CPC Class Codes: H01M 10/0525 Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
• CPC Class Codes: H01M 10/0562 Solid materials
• 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 2010/0495 Nanobatteries
• CPC Class Codes: H01M 4/0421 involving vapour deposition
• CPC Class Codes: H01M 4/0423 Physical vapour deposition
• CPC Class Codes: H01M 4/525 of mixed oxides or hydroxides containing iron, cobalt or nickel for inserting or intercalating light metals, e.g. LiNiO2, LiCoO2 or LiCoOxFy
• CPC Class Codes: H01M 4/5815 Sulfides
• CPC Class Codes: H01M 4/661 Metal or alloys, e.g. alloy coatings H01M4/669 take precedence
• 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
• CPC Class Codes: Y10T 29/49108 Electric battery cell making

Abstract

A method for forming a lithium-ion type battery including the steps of forming, over an at least locally conductive substrate, an insulating layer having a through opening; successively and conformally depositing a stack comprising a cathode collector layer, a cathode layer, an electrolyte layer, and an anode layer, this stack having a thickness smaller than the thickness of the insulating layer; forming, over the structure, an anode collector layer filling the space remaining in the opening; and planarizing the structure to expose the upper surface of the insulating layer.

Claims

1. A method for forming a lithium-ion type battery comprising the steps of:

(a) forming, over an at least locally conductive substrate an insulating layer comprising a through opening;

(b) successively and conformally depositing a stack comprising a cathode collector layer, a cathode layer, an electrolyte layer, and an anode layer, this stack having a thickness smaller than the thickness of the insulating layer;

(c) forming, over the structure, an anode collector layer filling the space remaining in the opening; and

(d) planarizing the structure to expose the upper surface of the insulating layer.

2. The method of claim 1, further comprising, after step (d), the steps of:

forming at least one protection layer over the structure and defining an opening in said protection layer, above the anode collector layer; and

forming a conductive region in the opening of the protection layer and above a portion of the protection layer.

3. The method of claim 2, further comprising a step of forming of a first contact on the conductive layer and of a second contact on the substrate.

4. The method of claim 1, further comprising, before step (c), a step of forming of a seed layer.

5. The method of claim 4, wherein the anode collector layer is formed by electrolytic growth at low temperature on the seed layer, the seed layer being formed of a stack of titanium and copper.

6. The method of claim 2, wherein the substrate is made of doped silicon or metal, the cathode collector layer is made of titanium, tungsten, molybdenum, tantalum, platinum, or of an alloy or a stack of these materials, the cathode layer is made of titanium lithium oxysulfide, of cobalt lithium oxide, or of any material capable of inserting lithium, the electrolyte layer is made of lithium phosphorus oxynitride, the anode layer is made of silicon, germanium, carbon, or an alloy or a stack of these materials, and the anode collector layer is made of copper.

7. The method of claim 1, wherein the cathode collector layer, the cathode layer, the electrolyte layer, and the anode layer are formed by physical vapor deposition.

8. The method of claim 2, wherein the protection layer is formed of a stack of a first layer made of ceramic, Al₂O₃, SiN, or ZrO₂, and of a second SiO₂ layer.

9. The method of claim 1, wherein the insulating layer has a thickness ranging between 5 and 30 μ

m, the cathode collector layer has a thickness ranging between 100 and 500 nm, the cathode layer has a thickness ranging between 1 and 10 μ

m, the electrolyte layer has a thickness ranging between 1 and 3 μ

m, and the anode layer has a thickness ranging between 10 and 800 nm.

10. A lithium-ion type battery, comprising:

an at least locally conductive substrate, supporting an insulating layer comprising a first through opening; and

along the walls and the bottom of the opening, a stack of a cathode collector layer, of a cathode layer, of an electrolyte layer, of an anode layer, and of an anode collector layer, the stack filling the first opening.