Abstract:
An approach is presented for designing a polymeric layer for nanometer scale thermo-mechanical storage devices. Cross-linked polyaryletherketone polymers are used as the recording layers in atomic force data storage devices, giving significantly improved performance when compared to previously reported cross-linked and linear polymers. The cross-linking of the polyaryletherketone polymers may be tuned to match thermal and force parameters required in read-write-erase cycles.

Description:
FIELD OF THE INVENTION 
     The present invention relates to the field of high-density data storage and read-back and more specifically to a data storage and read-back medium, a data storage and read-back system, and a data storage and read-back method. 
     BACKGROUND OF THE INVENTION 
     Current data storage and imaging methodologies operate in the micron regime. In an effort to store ever more information in ever-smaller spaces, data storage density has been increasing. In an effort to reduce power consumption and increase the speed of operation of integrated circuits, the lithography used to fabricate integrated circuits is pressed toward smaller dimensions and denser imaging. As data storage size increases and density increases and integrated circuit densities increase, there is a developing need for data storage and imaging methodologies that operate in the nanometer regime. 
     SUMMARY OF THE INVENTION 
     A first aspect of the present invention is a composition of matter, comprising: a cured resin comprising: one or more polyaryletherketone polymers; and one or more reactive diluents cross-linking the one or more polyaryletherketone polymers; and wherein the cured resin has a glass transition temperature of less than about 220° C. 
     A second aspect of the present invention is a method, comprising: pushing a probe, heated to at least 100° C., into a layer of a resin formed by curing a layer of one or more polyaryletherketone polymers and one or more reactive diluents; and removing the probe from the layer of the resin, resulting in formation of a deformed region in the layer of the resin. 
     A third aspect of the present invention is a method, comprising: bringing a thermal-mechanical probe into proximity with a layer of resin multiple times to induce deformed regions at points in the layer of the resin, the resin comprising one or more polyaryletherketone polymers cross-linked by one or more reactive diluent groups, the resin having a glass transition temperature of less than about 220° C., the thermal mechanical probe heated to a temperature of greater than about 100° C., the thermal mechanical probe heating the points in the layer of the resin and thereby writing information in the layer of the resin. 
     A fourth aspect of the present invention is a data storage device, comprising: a recording medium comprising a layer of a resin overlying a substrate, in which topographical states of the layer of the resin represent data, the resin comprising one or more polyaryletherketone polymers cross-linked by one or more reactive diluent groups, the resin having a glass transition temperature of less than about 220° C., the thermal mechanical probe heated to a temperature of greater than about 100° C., the thermal mechanical probe heating the points in the layer of the resin and thereby writing information in the layer of the resin; and a read-write head having one or more thermo-mechanical probes, each of the one or more thermo-mechanical probes including a resistive region locally exerting heat at a tip of the thermo-mechanical probe in response to electrical current being applied to the one or more thermo-mechanical probes; and a scanning system for scanning the read-write head across a surface of the recording medium. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       The features of the invention are set forth in the appended claims. The invention itself, however, will be best understood by reference to the following detailed description of an illustrative embodiment when read in conjunction with the accompanying drawings, wherein: 
         FIGS. 1A through 1C  illustrate the structure and operation of a tip assembly for a data storage device including the data storage medium according to the embodiments of the present invention; 
         FIG. 2  is an isometric view of a local probe storage array including the data storage medium according to the embodiments of the present invention; and 
         FIG. 3  is a diagram illustrating cross-linking of a polyaryletherketone polymer with a reactive diluent according to embodiments of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       FIGS. 1A through 1C  illustrate the structure and operation of a tip assembly  100  for a data storage device including the data storage medium according to the embodiments of the present invention. In  FIG. 1A , probe tip assembly  100  includes a U-shaped cantilever  105  having flexible members  105 A and  105 B connected to a support structure  110 . Flexing of members  105 A and  105 B provides for substantial pivotal motion of cantilever  105  about a pivot axis  115 . Cantilever  105  includes an indenter tip  120  fixed to a heater  125  connected between flexing members  105 A and  105 B. Flexing members  105 A and  105 B and heater  125  are electrically conductive and connected to wires (not shown) in support structure  110 . In one example, flexing members  105 A and  105 B and indenter tip  120  are formed of highly-doped silicon and have a low electrical resistance, and heater  125  is formed of lightly doped silicon having a high electrical resistance sufficient to heat indenter tip  120 , in one example, to between about 100° C. and about 500° C. when current is passed through heater  125 . The electrical resistance of heater  125  is a function of temperature. 
     Also illustrated in  FIG. 1A  is a storage medium (or a recording medium)  130  comprising a substrate  130 A, and a cured polyaryletherketone resin layer  130 B. In one example, substrate  130 A comprises silicon. Cured polyaryletherketone resin layer  130 B may be formed by solution coating, spin coating, dip coating or meniscus coating polyaryletherketone polymer and reactive diluent formulations and performing a curing operation on the resultant coating. In one example, cured polyaryletherketone resin layer  130 B has a thickness between about 10 nm and about 500 nm. The composition of cured polyaryletherketone resin layer  130 B is described infra. An optional penetration stop layer  130 C is shown between cured polyaryletherketone resin layer  130 B and substrate  130 A. Penetration stop layer  130 C limits the depth of penetration of indenter tip  120  into cured polyaryletherketone resin layer  130 B. 
     Turning to the operation of tip assembly  100 , in  FIG. 1A , an indentation  135  is formed in cured polyaryletherketone resin layer  130 B by heating indenter tip  120  to a writing temperature T W  by passing a current through cantilever  105  and pressing indenter tip  120  into cured polyaryletherketone resin layer  130 B. Heating indenter tip  120  allows the tip to penetrate the cured polyaryletherketone resin layer  103 B forming indentation  135 , which remains after the tip is removed. In a first example, the cured polyaryletherketone resin layer  130 B is heated by heated indenter tip  120 , the temperature of the indenter tip being not greater than about 500° C., to form indentation  135 . In a second example, the cured polyaryletherketone resin layer  130 B is heated by heated indented tip  120 , the temperature of the indenter tip being not greater than about 400° C., to form indentation  135 . In a third example, the cured polyaryletherketone resin layer  130 B is heated by heated indenter tip  120 , the temperature of the indenter tip being between about 200° C. and about 500° C., to form indentation  135 . In a fourth example, the cured polyaryletherketone resin layer  130 B is heated by heated indenter tip  120 , the temperature of the indenter tip being between about 100° C. and about 400° C., to form indentation  135 . As indentations  135  are formed, a ring  135 A of cured polyaryletherketone resin is formed around the indentation. Indentation  135  represents a data bit value of “1”, a data bit value of “0” being represented by an absence of an indentation. 
       FIGS. 1B and 1C  illustrate reading the bit value. In  FIGS. 1B and 1C , tip assembly  100  is scanned across a portion of cured polyaryletherketone resin layer  103 B. When indenter tip  120  is over a region of cured polyaryletherketone resin layer  130 B not containing an indentation, heater  125  is a distance D 1  from the surface of the cured polyaryletherketone resin layer (see  FIG. 1B ). When indenter tip  120  is over a region of cured polyaryletherketone resin layer  130 B containing an indentation, heater  125  is a distance D 2  from the surface of the cured polyaryletherketone resin layer (see  FIG. 1C ) because the tip “falls” into the indentation. D 1  is greater than D 2 . If heater  125  is at a temperature T R  (read temperature), which is lower than T W  (write temperature), there is more heat loss to substrate  130 A when indenter tip  120  is in an indentation than when the tip is not. This can be measured as a change in resistance of the heater at constant current, thus “reading” the data bit value. It is advantageous to use a separate heater for reading, which is mechanically coupled to the tip but thermally isolated from the tip. A typical embodiment is disclosed in Patent Application EP 05405018.2, 13 Jan. 2005. 
     “Erasing” (not shown) is accomplished by positioning indenter tip  120  in close proximity to indentation  135 , heating the tip to a temperature T E  (erase temperature), and applying a loading force similar to writing, which causes the previously written indent to relax to a flat state whereas a new indent is written slightly displaced with respect to the erased indent. The cycle is repeated as needed for erasing a stream of bits whereby an indent always remains at the end of the erase track. T E  is typically greater than T W . The erase pitch is typically on the order of the rim radius. In a first example, the cured polyaryletherketone resin layer  130 B is heated by heated indenter tip  120 , the temperature of the indenter tip is not greater than about 500° C., and the erase pitch is 10 nm to eliminate indentation  135 . In a second example, the cured polyaryletherketone resin layer  130 B is heated by heated indenter tip  120 , the temperature of the indenter tip is not greater than about 400° C., and the erase pitch is 10 nm to eliminate indentation  135 . In a third example, the cured polyaryletherketone resin layer  130 B is heated by heated indenter tip  120 , the temperature of the indenter tip is between about 200° C. and about 400° C., and the erase pitch is 10 nm to eliminate indentation  135 . In a fourth example, the cured polyaryletherketone resin layer  130 B is heated by heated indenter tip  120 , the temperature of the indenter tip is between about 200° C. and about 500° C., and the erase pitch is 10 nm to eliminate indentation  135 . 
       FIG. 2  is an isometric view of a local probe storage array  140  including the data storage medium according to the embodiments of the present invention. In  FIG. 2 , local probe storage array  140  includes substrate  145  having a cured polyaryletherketone resin layer  150  (similar to cured polyaryletherketone resin layer  130 B of  FIGS. 1A ,  1 B and  1 C), which acts as the data-recording layer. An optional tip penetration stop layer may be formed between cured polyaryletherketone resin layer  150  and substrate  145 . In one example, substrate  145  comprises silicon. Cured polyaryletherketone resin layer  150  may be formed by solution coating, spin coating, dip coating or meniscus coating uncured polyimide resin formulations and performing a curing operation on the resultant coating. In one example, cured polyaryletherketone resin layer  150  has a thickness between about 10 nm and about 500 nm and a root mean square surface roughness across a writeable region of cured polyimide resin layer  150  of less than about 1.0 nm across the cured polyimide resin layer. The composition of cured polyaryletherketone resin layer  150  is described infra. Positioned over cured polyaryletherketone resin layer  150  is a probe assembly  155  including an array of probe tip assemblies  100  (described supra). Probe assembly  155  may be moved in the X, Y and Z directions relative to substrate  145  and cured polyaryletherketone resin layer  150  by any number of devices as is known in the art. Switching arrays  160 A and  160 B are connected to respective rows (X-direction) and columns (Y-direction) of probe tip assemblies  100  in order to allow addressing of individual probe tip assemblies. Switching arrays  160 A and  160 B are connected to a controller  165  which includes a write control circuit for independently writing data bits with each probe tip assembly  100 , a read control circuit for independently reading data bits with each probe tip assembly  100 , an erase control circuit for independently erasing data bits with each probe tip assembly  100 , a heat control circuit for independently controlling each heater of each of the probe tip assembles  100 , and X, Y and Z control circuits for controlling the X, Y and Z movement of probe assembly  155 . The Z control circuit controls a contact mechanism (not shown) for contacting the cured polyaryletherketone resin layer  150  with the tips of the array of probe tip assemblies  100 . 
     During a write operation, probe assembly  155  is brought into proximity to cured polyaryletherketone resin layer and probe tip assemblies  100  are scanned relative to the cured polyaryletherketone resin layer. Local indentations  135  are formed as described supra. Each of the probe tip assemblies  100  writes only in a corresponding region  170  of cured polyaryletherketone resin layer  150 . This reduces the amount of travel and thus time required for writing data. 
     During a read operation, probe assembly  155  is brought into proximity to cured polyaryletherketone resin layer  150  and probe tip assemblies  100  are scanned relative to the cured polyaryletherketone resin layer. Local indentations  135  are detected as described supra. Each of the probe tip assemblies  100  reads only in a corresponding region  170  of cured polyaryletherketone resin layer  150 . This reduces the amount of travel and thus the time required for reading data. 
     During an erase operation, probe assembly  155  is brought into proximity to cured polyaryletherketone resin layer  150 , and probe tip assemblies  100  are scanned relative to the cured polyaryletherketone resin layer. Local indentations  135  are erased as described supra. Each of the probe tip assemblies  100  reads only in a corresponding region  170  of cured polyimide resin layer  150 . This reduces the amount of travel and thus time required for erasing data. 
     Additional details relating to data storage devices described supra may be found in the articles “The Millipede—More than one thousand tips for future AFM data storage,” P. Vettiger et al.,  IBM Journal of Research and Development.  Vol. 44 No. 3, May 2000 and “The Millipede—Nanotechnology Entering Data Storage,” P. Vettiger et al.,  IEEE Transaction on Nanotechnology,  Vol. 1, No, 1, March 2002. See also U.S. Patent Publication 2005/0047307, Published Mar. 3, 2005 to Frommer et al. and U.S. Patent Publication 2005/0050258, Published Mar. 3, 2005 to Frommer et al., both of which are hereby included by reference in their entireties. 
     Turning to the composition of cured polyaryletherketone resin layer  130 B of  FIGS. 1A through 1C . It should be understood that for the purposes of the present invention curing a polymer implies cross-linking the polymer to form a cross-linked polymer or resin. 
     The polyaryletherketone resin medium or imaging layer of the embodiments of the present invention advantageously meets certain criteria. These criteria include high thermal stability to withstand millions of write and erase events, low wear properties (low pickup of material by tips), low abrasion (tips do not wear out), low viscosity for writing, glassy character with no secondary relaxations for long data bit lifetime, and shape memory for erasability. 
     Cured polyaryletherketone resins according to embodiments of the present invention have high temperature stability while maintaining a low glass transition temperature (Tg). In a first example, cured polyaryletherketone resins according to embodiments of the present invention have a Tg of less than about 220° C. In a second example, cured polyaryletherketone resins according to embodiments of the present invention have a Tg of less than about 180° C. In a third example, cured polyaryletherketone resins according to embodiments of the present invention have a Tg of between about 150° C. and about 180° C. In a fourth example, cured polyaryletherketone resins according to embodiments of the present invention have a Tg of between about 100° C. and about 150° C. 
     Wear and erasability of the media were improved by cross-linking the polyimide oligomers without increasing the T g , which was unexpected. By placing the cross-linking sites at the chain ends, the molecular weight between cross-links of polyaryletherketone polymer is predefined and therefore cross-linking was found to have a lesser effect upon the glass transition temperature than was previously thought. 
     Further control over the cross-link density was achieved by adding controlled amounts of reactive diluents described infra that enhance cross-linking. These reactive diluents formed a high density of cross-links that enhanced the wear properties of the polyimide medium without greatly increasing the Tg. 
     The glass transition temperature was adjusted for good write performance. To optimize the efficiency of the write process there should be a sharp transition from the glassy state to the rubbery state. A sharp transition allows the cured resin to flow easily when a hot tip is brought into contact and quickly return to the glassy state once the hot tip is removed. However, too high a T g  leads to high write currents and damage to the probe tip assemblies described supra. 
     A formulation of polyaryletherketone polymer comprises one or more polyaryletherketone polymers and one or more reactive diluents. Each of the polyaryletherketone polymers has the structure: 
                                
wherein R 1  is selected from the group consisting of
 
                                
wherein R 2  is selected from the group consisting of
 
                                
wherein R 3  is selected from the group consisting of mono(arylacetylenes) including:
 
     
       
                 
         
             
             
         
      
     
     In one example, polyaryletherketone polymers according to embodiments of the present invention advantageously have a molecular weight between about 1,000 Daltons and about 20,000 Daltons. (For the purpose of describing the present invention Daltons and grams/mole (g/mol) may be used interchangeably). 
     Each of the reactive diluents is selected from the group consisting of poly(arylacetylene)s including 
                                
and poly(arylacetylene) ethers and poly(arylacetylene) poly ethers, including
 
     
       
                 
         
             
             
         
      
     
     In one example, reactive diluents according to embodiments of the present invention advantageously have a molecular weight greater than about 650 Daltons. 
     The endgroups R 3  having the structures (XIII) and (XIV) react during thermal curing with the reactive diluents to cross-link the polyaryletherketone polymers into a polyaryletherketone resin. Note reactive diluent (XV) is an example of a reactive diluent that provides three cross-linking sites (as illustrated in  FIG. 3 ), reactive diluent (XVII) is an example of a reactive diluent that provides four cross-linking sites, reactive diluent (XVIII) is an example of a reactive diluent that provides five cross-linking sites, and reactive diluent (XVI) is an example of a reactive diluent that provides six cross-linking sites. There is also some endgroup to endgroup linking in the cured resin. 
     In one example, reactive diluent derivatives comprise between about 20% by weight and about 40% by weight of the cured polyaryletherketone resin. In one example, curing is performed between about 250° C. and about 400° C. 
       FIG. 3  is a diagram illustrating cross-linking of a polyimide resin with a reactive diluent according to embodiments of the present invention. In  FIG. 3 , a mixture of (i) straight chain polyaryletherketone polymer  250  of repeating units n and having two reactive endgroups  255  (ii) a reactive diluent  260  having three reactive functionalities  265  is heat cured to produce a cross-linked polyaryletherketone resin  270 . In polyaryletherketone resin  270 , polyaryletherketone polymers  250  are linked to each other through respective reactive endgroups; polyaryletherketone polymers  250  are linked to reactive diluents  260  through respective reactive endgroups, and reactive diluents  260  are linked to each other through respective reactive endgroups. Although Tg is usually a function of molecular weight and cross-link density, in this case it is largely independent of the percentage by weight of reactive diluent in the polyaryletherketone polymer/reactive diluent mixture. 
     Synthesis Examples 
     All materials were purchased from Aldrich and used without further purification unless otherwise noted. Bisphenol-A, dihydroxyphenylether, 4,4′-difluorobenzophenone, and resorcinol were sublimed under vacuum. 
     Synthesis of the endgroup 3-(phenylethynyl)phenol (Structure XIII): 
     
       
                 
         
             
             
         
      
     
     3-Iodophenol (5.00 g, 22.7 mmol), bis(triphenylphopine)palladium(II) dichloride (PdCl 2 (PPh 3 ) 2 ) (160 mg, 0.23 mmol, 1 mol %), PPh 3  (420 mg, 1.60 mmol, 7 mol %), and CuI (220 mg, 1.16 mmol, 5 mol %) were dissolved in triethylamine (NEt 3 ) (150 mL) and the resulting suspension was treated with three cycles of evacuation and refilling with N 2 . Phenylacetylene (3.1 mL, 2.9 g, 28.4 mmol, 1.25 eq) was added by syringe, and the reaction mixture was again treated with three cycles of evacuation and refilling with N 2 . The reaction mixture was then stirred and heated to 70° C. using an oilbath for 38 h. The reaction was cooled, and the excess NEt 3  was removed under reduced pressure. The remaining solids were extracted with 3×50 mL portions of diethyl ether, which were filtered and then evaporated. The crude product was purified by column chromatography (silica, 3:1 hexanes-ethyl acetate) to give 4.1 g of an orange solid. Further purification was accomplished by sublimation (100° C., 28 mTorr) to give 3-(phenylethynyl)phenol as a white solid (3.3 g. 75% yield). 
     Synthesis of the endgroup 4-fluoro-4′-(phenylethynyl)benzophenone (Structure XV): 
     
       
                 
         
             
             
         
      
     
     (i) 4-bromo-4′-fluorobenzophenone: fluorobenzene (6.89 g, 71.7 mmol), 4-bromobenzoyl chloride (7.86 g, 35.8 mmol), and aluminum chloride (4.78 g, 35.8 mmol) were combined and stirred for 24 h at room temperature. The resulting mixture was poured over ice, and then filtered. The solid was dissolved in hot ethanol, treated with decolorizing charcoal, and filtered; white crystals of the title compound formed upon cooling of the ethanol solution and were isolated by filtration. 
     (ii) In an inert atmosphere glovebox, 4-bromo-4′-fluorobenzophenone (10 g, 35.8 mmol), PdCl 2 (PPh 3 ) 2  (250 mg), CuI (680 mg), phenylacetylene (4.02 g, 1.1 eq), triethylamine (3.6 g, 1 eq), and toluene (25 mL) were combined. The flask was closed and heated to 70° C. for 24 h. The mixture was poured over ice and extracted with methylene chloride, which was separated and evaporated. The residue was recrystallized twice from hot ethanol using decolorizing charcoal to give the title product as white crystals. 
     Example synthesis of a polyaryletherketone polymer (Structure XX): 
     
       
                 
         
             
             
         
      
     
     To a 100-mL, three necked, round-bottomed flask fitted with a nitrogen inlet, a Dean-Stark trap fitted with a condenser, and an overhead stirrer, 0.0098 mol of bisphenol-A, 0.02 mol anhydrous potassium carbonate, and varying amounts of 4,4′-difluorobenzophenone and 4-fluoro-4′-phenylethynylbenzophenone were added in different proportions, depending on the targeted molecular weight. Additionally, 60 mL of anhydrous DMF and 10 mL of anhydrous toluene were added and the reaction mixture was refluxed at 120° C. for 6-8 hours, then the reaction was subsequently brought to 140° C. for 8-10 hours, then the temperature was increased to 150° C. for the remainder of the 24-hour reaction period. Water, the reaction byproduct, was removed by azeotropic distillation with toluene. The product was precipitated in acidified methanol. 
       1 H nuclear magnetic resonance (NMR) spectra were acquired in deuterated DMSO or methylene chloride on the Bruker Avance 400 spectrometer. 4-fluoro-4′-phenylethynylbenzophenone:  1 H NMR: δ (ppm)=7.87 (m, 2H), 7.81 (d, 2H), 7.69 (d, 2H), 7.61 (m, 2H), 7.44 (m, 1H), 7.43 (m, 2H), 7.24 (t, 2H). Bisphenol-A Polyaryletherketone:  1 H NMR: δ (ppm) endcap signals=7.83 (s, 2H), 7.68 (d, 2H), 7.61 (s, 2H), 7.44 (b, 1H), 7.43 (b, 2H); backbone signals=7.80 (d, 2H), 7.33 (d, 2H), 7.08 (b, 2H), 7.05 (b, 2H), 1.74 (s, 6H) 
     Molecular weights were easily adjusted by using different proportions of monomers and endcaps and several different molecular weight polymers were prepared. Molecular weights, relative to polystyrene standards, were measured using a Waters 150 CV Plus Gel Permeation Chromatograph (GPC). The measurements were taken at room temperature using THF as the mobile phase in the column. 
     
       
         
               
             
               
               
               
               
               
             
               
               
               
               
               
             
           
               
                 TABLE I 
               
             
             
               
                   
               
               
                 Calculated Molecular Weight (Structure XX) by GPC and NMR 
               
             
          
           
               
                   
                 Molecular Weight 
                 &lt;M n &gt; by GPC 
                 PDI 
                 &lt;M n &gt; by NMR 
               
               
                   
                 (g/mol) 
                 (×10 −3  g/mol) 
                 (%) 
                 (×10 −3  g/mol) 
               
               
                   
                   
               
             
          
           
               
                   
                 4,000 
                 6.3 
                 1.55 
                 3.9 
               
               
                   
                 8,000 
                 13.3 
                 1.63 
                 6.7 
               
               
                   
                 16,000 
                 25.5 
                 1.75 
                 9.6 
               
               
                   
                 32,000 
                 39.2 
                 1.58 
                 — 
               
               
                   
                   
               
             
          
         
       
     
     Thermal decomposition of samples was recorded by the TA instruments Hi-Res TGA 2950 Thermogravimetric Analysis. Measurements were conducted in a nitrogen atmosphere at a heating rate of 10° C./min and samples were ultimately heated to 500° C. Thermal transitions were reported by the TA instruments DSC 2920 Differential Scanning Calorimeter. The samples were heated at a rate of 10° C./min with a temperature range of 350° C. 
     
       
         
               
             
               
               
               
             
           
               
                 TABLE II 
               
             
             
               
                   
               
               
                 Thermal Data from DSC 
               
             
          
           
               
                   
                 Composition and MW 
                   
               
               
                   
                 in (g/mol) 
                 Tg (° C.) 
               
               
                   
                   
               
               
                   
                 Structure XIX, 4,000 
                 154 
               
               
                   
                 Structure XIX, 8,000 
                 151 
               
               
                   
                 Structure XIX, 16,000 
                 154 
               
               
                   
                 Structure XIX, 8,000 
                 151 
               
               
                   
                 Mixed with Structure 
               
               
                   
                 XVI but not cured 
               
               
                   
                 Structure XIX, 8,000 
                 170 
               
               
                   
                 Mixed with 30% by 
               
               
                   
                 weight Structure XVI 
               
               
                   
                 and cured 
               
               
                   
                   
               
             
          
         
       
     
     The glass transition temperatures of the compositions range from 151° C. for the 8,000 g/mol structure XIX polymer and uncured 8,000 g/mol structure XIX polymer mixed with reactive diluent structure XVII to 170° C. for the cured resin of 8,000 g/mol structure XX polymer mixed with 30% reactive diluent structure XVI. 
     For TGA, at 420° C., the cured resin of 8,000 g/mol structure XIX polymer mixed with 30% reactive diluent structure XVI had experienced 1% decomposition, and only 5% had decomposed after reaching a temperature at 490° C. 
     It can be concluded that polyaryletherketone resins according to embodiments of the present invention exhibit excellent thermal stability. 
     Swelling (as a percentage increase in volume) experiments were conducted to determine the solvent resistance properties of the cured polyaryletherketone resins. Swelling is important, because the process for fabricating storage devices described in  FIGS. 1A ,  1 B, and  1 C and  2  require the polyaryletherketone resin storage media be subjected to solvent cleaning procedures. 
     
       
         
               
             
               
               
               
             
           
               
                 TABLE III 
               
             
             
               
                   
               
               
                 Thermal Data from DSC 
               
             
          
           
               
                   
                 Composition and MW 
                   
               
               
                   
                 in (g/mol) 
                 Swelling Results 
               
               
                   
                   
               
               
                   
                 Structure XIX, 4,000 
                 After 4 hours, 54% 
               
               
                   
                   
                 dissolved in THF 
               
               
                   
                   
                 After 4 hours 785% 
               
               
                   
                   
                 increase in volume in 
               
               
                   
                   
                 NMP 
               
               
                   
                 Structure XIX, 8,000 
                 Dissolved in less than 1 
               
               
                   
                   
                 hour in both THF and 
               
               
                   
                   
                 NMP 
               
               
                   
                 Structure XIX, 16,000 
                 Dissolved in 10 minutes 
               
               
                   
                   
                 in THF 
               
               
                   
                   
                 Dissolved in 30 minutes 
               
               
                   
                   
                 in NMP 
               
               
                   
                 Structure XIX, 8,000 
                 After 24 hours, 18% 
               
               
                   
                 Mixed with Structure 
                 increase in volume in 
               
               
                   
                 XVI and cured 
                 THF 
               
               
                   
                   
                 After 24 hours, 6% 
               
               
                   
                   
                 increase in volume in 
               
               
                   
                   
                 NMP 
               
               
                   
                   
               
             
          
         
       
     
     Without cross-linking with a reactive diluent, all structure XIX polyaryletherketone polymers dissolved in less than six hours. However, there was a trend of increased solvent resistance with increased endcap incorporation, as the 4,000 g/mol polymer was much more resistant than the 16,000 g/mol polymer with a lower cross-linking density. By contrast, the cured resin of 8,000 g/mol structure XIX polymer mixed with 30% reactive diluent structure XVI exhibit a minor increase in volume of 18% in THF and 6% in NMP after 24 hour immersion. 
     Thus, the embodiments of the present invention provide data storage and imaging methodologies that operate in the nanometer regime. 
     The description of the embodiments of the present invention is given above for the understanding of the present invention. It will be understood that the invention is not limited to the particular embodiments described herein, but is capable of various modifications, rearrangements and substitutions as will now become apparent to those skilled in the art without departing from the scope of the invention. Therefore, it is intended that the following claims cover all such modifications and changes as fall within the true spirit and scope of the invention.