Data storage medium and method for high density data storage

Abstract

A composition of matter for a recording medium in atomic force data storage devices. The composition includes polyimide oligomers having covalently bonded monomers forming a backbone, the oligomer thermally stable to at least 400° C.; one or more covalent bonding cross-linking moieties incorporated into the polyimide oligomer; and one or more hydrogen bonding cross-linking moieties incorporated into the polyimide oligomer. The covalent and hydrogen bonding cross-linking of the polyimide oligomers may be tuned to match thermal and force parameters required in read-write-erase cycles.

1 . A composition of matter, comprising:
 polyimide oligomers comprising covalently bonded monomers, said monomers forming a backbone, said polyimide oligomers thermally stable to at least 400° C.;   one or more covalent bonding cross-linking moieties incorporated into said polyimide oligomers; and   one or more hydrogen bonding cross-linking moieties incorporated into said polyimide oligomers.   
     
     
         2 . The composition of  claim 1 , wherein said one or more hydrogen bonding cross-linking moieties are located along said backbone. 
     
     
         3 . The composition of  claim 2 , wherein said one or more hydrogen bonding cross-linking moieties are selected from the group consisting of 
       
         
           
           
               
               
           
         
       
       and moieties derived from imidazolyl, pyrazolyl, pyrazinyl, pyrimidinyl, pyridazinyl indazoyl, purinyl, phthalazinyl, naphthyridinyl, quinoxalinyl, quinazolinyl, 1,2,3-triazolyl, 1,2,4-triazolyl thiazolyl, isothiazolyl 1,3,5-triazinyl, 1,2,4-triazinyl, 1,2,3-triazinyl, pyrido[3,4-b]-pyridinyl, pyrido[3,2-b]-pyridinyl, pyrido[4,3-b]pyridinyl, purinyl, cinnolinyl, pteridinyl, beta-carbolinyl, phenazinyl, 1,7-phenanthrolinyl, 1,10-phenanthrolinyl, 4,7-phenanthrolinyl, phenarsazinyl, isothiazolyl, thienyl, and thianthrenyl imide. 
     
     
         4 . The composition of  claim 1 , whereon said one or more hydrogen bonding cross-linking moieties are located at terminal ends of said backbone. 
     
     
         5 . The composition of  claim 5 , wherein said one or more hydrogen bonding cross-linking moieties are selected from the group consisting of 
       
         
           
           
               
               
           
         
       
       moieties derived from 3,5-diamino-1,2,4-triazole, 2,6-diaminopurine, 2,6-diamino-8-purinol, 2,3-diaminopyridine, unsaturated heterocyclic diamines derived by reduction of 2-amino-6-nitrobenzothiazole, 2-amino-5-(4-nitrophenylsulfonyl)thiazole, 2-amino-5-nitropyrimidine, 2-amino-5-nitrothiazole, or 3-amino-4-pyrazole carbonitrile, and moieties derived from ammonia amination of 2-amino-5-bromopyrimidine, 2-amino-5-bromothiazole, 2-amino-4-chlorobenzothiazole, 2-amino-6-chlorobenzothiazole, 2-amino-4-(4-chlorophenyl)thiazole, 2-amino-6-chloropurine, or 2-amino-6-fluorobenzothiazole. 
     
     
         6 . The composition of  claim 1 , wherein said covalent bonding cross-linking moieties are located along said backbone. 
     
     
         7 . The composition of  claim 6  wherein said covalent bonding cross-linking moieties have the structure: 
       
         
           
           
               
               
           
         
       
     
     
         8 . The composition of  claim 1 , wherein said covalent bonding cross-linking moieties are located at terminal ends of said backbone. 
     
     
         9 . The composition of  claim 8 , wherein said covalent bonding cross-linking moieties have the structure: 
       
         
           
           
               
               
           
         
       
     
     
         10 . The composition of  claim 1 , further including a reactive diluent, said reactive diluent consisting of 
       
         
           
           
               
               
           
         
       
       where R 1 , R 2  and R 3  are each independently selected from the group consisting of hydrogen, alkyl groups, aryl groups, cycloalkyl groups, alkoxy groups, aryloxy groups, alkylamino groups, arylamino groups, alkylarylamino groups, arylthio, alkylthio groups and 
       
         
           
           
               
               
           
         
       
     
     
         11 . A method, comprising:
 pushing a probe, heated to at least 100° C., into a cross-linked resin layer formed by curing a layer of the composition of  claim 1 ; and   removing said probe from said resin layer, resulting in formation of a deformed region in said resin layer.   
     
     
         12 . The method of  claim 11 , said composition further including covalent bonding cross-linking moieties located along said backbone and wherein after said curing, said resin layer is cross-linked by said covalent bonding cross-linking moieties. 
     
     
         13 . The method of  claim 11 , said composition further including covalent bonding cross-linking moieties located at terminal ends of said backbone and wherein after said curing, said resin layer is cross-linked by said covalent bonding cross-linking moieties. 
     
     
         14 . The method of  claim 11 , said composition, further including a reactive diluent, wherein said polyimide oligomers are covalently cross-linked by reactive diluent groups derived from said reactive diluent during said curing. 
     
     
         15 . A method, comprising:
 bringing a thermal-mechanical probe into proximity with a cross-linked resin layer multiple times to induce deformed regions at points in said resin layer, said resin layer formed by curing a layer of the composition of  claim 1 , said thermal mechanical probe heating said points in said resin layer above about 100° C. to write information in said resin layer.   
     
     
         16 . The method of  claim 15 , further including:
 bringing said thermal-mechanical probe into proximity with said points in said resin layer to read said information.   
     
     
         17 . The method of  claim 16 , further including:
 bringing said thermal-mechanical probe into proximity with one or more of said deformed regions in said resin layer, said thermal mechanical probe heating said one or more of said deformed regions to above about 100° C. to deform said one or more of said deformed regions in such a way as to eliminate said one or more deformed regions to erase said information.   
     
     
         18 . The method of  claim 17 , further including:
 repeatedly writing, reading and erasing information at said points in said resin layer.   
     
     
         19 . A data storage device, comprising:
 a recording medium for storing data, said recording medium comprising a resin layer overlying a substrate, said data represented by topographical states of said resin layer, said resin layer comprising a thermally cured layer of the composition of  claim 1 ;   a read-write head for reading and writing data to said recording medium, said read-write head having one or more thermo-mechanical probes, each of said thermo-mechanical probes including an electrical resistive heating region; and   means for scanning said read-write head across a surface of said recording medium.   
     
     
         20 . The data storage device of  claim 19 , wherein:
 said one or more thermal-mechanical probes are arranged in a two dimensional array; and   said data storage device further including:
 means for independently applying electrical current to respective resistive heating regions of each of said thermo-mechanical probes; 
 means for independently applying an electrostatic force on each of said thermo-mechanical probes; 
 means for independently writing data bits to said recording medium with each of said one or more thermo-mechanical probes; and 
 means for independently reading data bits from said recording medium with each of said one or more thermo-mechanical probes. 
   
     
     
         21 . The data storage device of  claim 20 , further including:
 means for contacting said recording medium with respective tips of said one or more thermo-mechanical probes.   
     
     
         22 . A composition of matter comprising:
 a backbone structured as E 1 A 1 -A 2 -A 3 - . . . -A N E 2 , wherein N is between about 10 and about 45, wherein A 1 -A 2 -A 3 - . . . -A N  is a linearly connected sequence of N covalently bonded monomeric backbone units, wherein each of A 1 , A 2 , A 3  . . . A N  is independently either a hydrogen bonding cross-linking moiety, a covalently bonding cross-linking moiety or a non-cross-linking moiety and E1 and E2 are terminal cross-linking moieties.   
     
     
         23 . The composition of matter of  claim 22 , wherein E 1  and E 2  are both covalently bonding cross-linking moieties. 
     
     
         24 . The composition of matter of  claim 22 , wherein E 1  and E 2  are both hydrogen-bonding cross-linking moieties. 
     
     
         25 . A method, comprising:
 bringing a thermal-mechanical probe into proximity with a cross-linked resin layer multiple times to induce deformed regions at points in said resin layer, said resin layer formed by curing a layer of the composition of  claim 22 , said thermal mechanical probe heating said points in said resin layer above about 100° C. to write information in said resin layer.   
     
     
         26 . The method of  claim 25 , further including:
 bringing said thermal-mechanical probe into proximity with said points in said resin layer to read said information.   
     
     
         27 . The method of  claim 26 , further including:
 bringing said thermal-mechanical probe into proximity with one or more of said deformed regions in said resin layer, said thermal mechanical probe heating said one or more of said deformed regions to above about 100° C. to deform said one or more of said deformed regions in such a way as to eliminate said one or more deformed regions to erase said information.   
     
     
         28 . A data storage device, comprising:
 a recording medium for storing data, said recording medium comprising a resin layer overlying a substrate, said data represented by topographical states of said resin layer, said resin layer comprising a thermally cured layer of the composition of  claim 22 ;   a read-write head for reading and writing data to said recording medium, said read-write head having one or more thermo-mechanical probes, each of said thermo-mechanical probes including an electrical resistive heating region; and   means for scanning said read-write head across a surface of said recording medium.   
     
     
         29 . The data storage device of  claim 28 , wherein:
 said one or more thermal-mechanical probes are arranged in a two dimensional array; and   said data storage device further including:
 means for independently applying electrical current to respective resistive heating regions of each of said thermo-mechanical probes; 
 means for independently applying an electrostatic force on each of said thermo-mechanical probes; 
 means for independently writing data bits to said recording medium with each of said one or more thermo-mechanical probes; and 
 means for independently reading data bits from said recording medium with each of said one or more thermo-mechanical probes. 
   
     
     
         30 . The data storage device of  claim 29 , further including:
 means for contacting said recording medium with respective tips of said one or more thermo-mechanical probes.