METHOD FOR FORMING A LITHIUM-ION TYPE BATTERY

• US 20140038028A1
• Filed: 08/02/2013
• Published: 02/06/2014
• Est. Priority Date: 08/03/2012
• Status: Active Grant

• Current Assignee: STMicroelectronics International N.V. (STMicroelectronics NV)
• Original Assignee: STMicroelectronics SAS (STMicroelectronics NV)
• Inventors: Genard, Dominique
• Granted Patent: US 9,406,970 B2
• Time in Patent Office: Days
• US Class Current: 429/152
• 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 10/0585 of accumulators having only flat construction elements, i.e. flat positive electrodes, flat negative electrodes and flat separators
• CPC Class Codes: H01M 4/0423 Physical vapour deposition
• 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 for manufacturing a lithium-ion type battery including the steps of forming in a substrate a recess having lateral walls having a re-entrant profile; depositing, by successive non-conformal physical vapor depositions, a stack of the different layers forming a lithium-ion battery, this stack having a thickness smaller than the depth of the recess; depositing on the structure a filling layer filling the space remaining in the recess; and planarizing the structure to expose the upper surface of the stack.

Claims

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

(a) forming in a substrate a recess having lateral walls having a re-entrant profile;

(b) depositing, by successive non-conformal physical vapor depositions, a stack of different layers forming a lithium-ion type battery, this stack having a thickness smaller than the depth of the recess;

(c) depositing on the structure a filling layer filling the space remaining in the recess; and

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

2. The method of claim 1, wherein the substrate is made of silicon, uniformly coated with an insulating layer after the forming of the recess.

3. The method of claim 1, wherein the stack comprises at least a cathode collector layer, a cathode layer, an electrolyte layer, an anode layer, and an anode collector layer, in this order or in the reverse order.

4. The method of claim 3, wherein the substrate is made of doped silicon or of metal, the cathode collector layer made of titanium, of tungsten, of molybdenum, of tantalum, of platinum, of aluminum, or of copper, or of an alloy or a stack of these materials, the cathode layer is made of lithium titanium oxysulphide, of lithium cobalt oxide, of vanadium oxide, or of any material capable of inserting lithium, the electrolyte layer is made of lithium phosphorus oxynitride, of LiSON, of LiSiPON, the anode layer is made of silicon, of germanium, of carbon, of metal Li, of TiOx, or of a stack or of an alloy of these materials, and the anode collector layer is made of copper or of aluminum.

5. The method of claim 1, wherein 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.

6. An assembly of a pair of batteries obtained by the method of claim 1, wherein a first battery is assembled head-to-tail with a second battery, each of the batteries being used as a protection cap for the other.

7. The assembly of claim 6, wherein the order of deposition of the layers is reversed between the first and second batteries.

8. The assembly of claim 6, wherein the connection with the back side of each battery is provided by a via crossing the substrate of this battery.