Thin film battery fabrication using laser shaping

Abstract

A method of fabricating a battery comprises selecting a battery substrate having cleavage planes, and depositing at least one battery component film comprising a metal or metal compound. A plurality of pulsed laser beam bursts from a femtosecond laser source that is set to provide a pulsed laser beam having an irradiance level of from about 10 to about 800 J/cm 2 , are applied to the battery component film to vaporize at least a portion of the metal or metal compound of the battery component film substantially without causing fractures along the cleavage planes of the battery substrate.

What is claimed is: 
     
         1 . A method of fabricating a battery on a battery substrate, the method comprising:
 (a) selecting a battery substrate having cleavage planes;   (b) depositing at least one battery component film on the battery substrate, the battery component film comprising a metal or metal compound; and   (c) applying to the battery component film, a plurality of pulsed laser beam bursts from a femtosecond laser source that is set to provide a pulsed laser beam having an irradiance level of from about 10 to about 800 J/cm 2 , to vaporize at least a portion of the metal or metal compound of the battery component film substantially without causing fractures along the cleavage planes of the battery substrate.   
     
     
         2 . A method according to  claim 1  wherein the femtosecond laser source is set to provide a pulsed laser beam having a pulse duration of from about 50 to about 600 femtoseconds. 
     
     
         3 . A method according to  claim 1  wherein the femtosecond laser source is set to provide a pulsed laser beam having an energy of from about 2 microjoules to about 100 millijoules. 
     
     
         4 . A method according to  claim 1  wherein the femtosecond laser source is set to provide a pulsed laser beam having a pulse repetition rate of from about 50 to about 1000 Hz. 
     
     
         5 . A method according to  claim 1  wherein the femtosecond laser source is set to provide a pulsed laser beam having a peak laser fluence of less than 0.2 J/cm 2 . 
     
     
         6 . A method according to  claim 1  wherein the battery substrate comprises a mica substrate. 
     
     
         7 . A method according to  claim 1  wherein the femtosecond laser source is set to provide pulsed laser beam bursts having an energy density of less than 1.5 J/cm 2  or a peak laser fluence of at least about 8 J/cm 2 . 
     
     
         8 . A method according to  claim 7  wherein the battery substrate comprises a mica substrate and the battery component films have a total thickness of about 40 microns. 
     
     
         8 . A method according to  claim 1  wherein (b) comprises depositing a battery component film comprising at least one of:
 (i) an electrode film that is a cathode film comprising at least one of: lithium cobalt oxide, lithium nickel oxide, lithium manganese oxide, lithium iron oxide, lithium cobalt nickel oxide, vanadium pentoxide and titanium disulfide; and 
 (ii) an electrolyte film comprising amorphous lithium phosphorous oxynitride. 
 
     
     
         10 . A method according to  claim 1  comprising applying the pulsed laser beam bursts in a dry box or dry room which is substantially absent oxygen or moisture. 
     
     
         11 . A method of fabricating a battery on a battery substrate, the method comprising:
 (a) selecting a battery substrate having cleavage planes;   (b) depositing at least one battery component film on the battery substrate, the battery component film comprising a metal or metal compound; and   (c) applying to the battery component film, a plurality of pulsed laser beam bursts from a femtosecond laser source that is set to provide a pulsed laser beam having (i) an irradiance level of from about 10 to about 800 J/cm 2 , and (ii) a pulse duration of from about 50 to about 600 femtoseconds,   whereby at least a portion of the metal or metal compound of the battery component film is vaporized substantially without causing fractures along the cleavage planes of the battery substrate.   
     
     
         12 . A method according to  claim 11  wherein the femtosecond laser source is set to provide a pulsed laser beam having at least one of:
 (i) an energy of from about 2 microjoules to about 100 millijoules; and 
 (ii) a peak laser fluence of less than 0.2 J/cm 2 . 
 
     
     
         13 . A method according to  claim 11  wherein the femtosecond laser source is set to provide a pulsed laser beam having a pulse repetition rate of from about 50 to about 1000 Hz. 
     
     
         14 . A method according to  claim 11  wherein the femtosecond laser source is set to provide pulsed laser beam bursts having an energy density of less than 1.5 J/cm 2  or a peak laser fluence of at least about 8 J/cm 2 . 
     
     
         15 . A method according to  claim 11  wherein the battery substrate comprises a mica substrate. 
     
     
         16 . A method of fabricating a battery on a battery substrate, the method comprising:
 (a) selecting a battery substrate having cleavage planes;   (b) depositing at least one battery component film on the battery substrate, the battery component film comprising a metal or metal compound; and   (c) applying to the battery component film, a plurality of pulsed laser beam bursts from a femtosecond laser source that is set to provide an energy density of less than 1.5 J/cm 2  or a peak laser fluence of at least about 8 J/cm 2 ,   whereby at least a portion of the metal or metal compound of the battery component film is vaporized substantially without causing fractures along the cleavage planes of the battery substrate.   
     
     
         17 . A method according to  claim 16  wherein the femtosecond laser source is set to provide a pulsed laser beam having at least one of:
 (i) an irradiance level of from about 10 to about 800 J/cm 2 , and 
 (ii) a pulse duration of from about 50 to about 600 femtoseconds. 
 
     
     
         18 . A method according to  claim 16  wherein the femtosecond laser source is set to provide a pulsed laser beam having at least one of:
 (i) an energy of from about 2 microjoules to about 100 millijoules; and 
 (ii) a peak laser fluence of less than 0.2 J/cm 2 .