초록 ▼

ESD is prevented in a disk drive suspension electrical interconnect having plural pairs of conductive traces supported by an insulative film by disposing a material having a lower resistivity than the insulative film but not so low that the conductive traces are shunted. The material is disposed in

ESD is prevented in a disk drive suspension electrical interconnect having plural pairs of conductive traces supported by an insulative film by disposing a material having a lower resistivity than the insulative film but not so low that the conductive traces are shunted. The material is disposed in or on the film and is to be connected to ground.

대표청구항 ▼

What is claimed is: 1. A disk drive suspension assembly comprising a signal conductor and a spring element for biasing a slider into operating proximity with a disk, said assembly having a surface tending to develop an electrostatic discharge potential, and a surface resistivity modifying agent at

What is claimed is: 1. A disk drive suspension assembly comprising a signal conductor and a spring element for biasing a slider into operating proximity with a disk, said assembly having a surface tending to develop an electrostatic discharge potential, and a surface resistivity modifying agent at said assembly surface, said agent being electrically coupled to ground and present at said assembly surface in an electrostatic discharge potential lowering amount effective for continually leaking charge to ground at a rate greater than the rate of accumulation of electrostatic charge on said assembly surface while avoiding shunting of said conductor, said surface resistivity modifying agent being in contact with said conductor. 2. The disk drive suspension assembly according to claim 1, in which said modifying agent provides said assembly surface a surface resistivity between about 100,000 ohms per square and 1000 megohms per square. 3. The disk drive suspension assembly according to claim 2, in which said modifying agent comprises a metal oxide. 4. The disk drive suspension assembly according to claim 3, in which said metal oxide is coated on said assembly surface. 5. The disk drive suspension assembly according to claim 3, in which said metal oxide is incorporated into said assembly surface. 6. The disk drive suspension assembly according to claim 3, in which said metal oxide comprises chromium oxide, tin oxide, nickel oxide, lead oxide or copper oxide. 7. The disk drive suspension assembly according to claim 2, in which said modifying agent comprises a metal in an electrostatic potential dissipating amount at said surface. 8. The disk drive suspension assembly according to claim 7, in which said modifying agent metal comprises one or more of Silver Barium Beryllium Bismuth Cadmium Mercury Indium Iridium Gold Chromium Nickel Cobalt Tin Aluminum Copper Stainless Steel alloy Iron-Nickel-Chrome alloy Tin-Lead alloy Platinum Tin-Lead-Silver Monel alloy R-Monel alloy K-Monel an alloy Incoloy alloy Inconel alloy 326 Monel alloy KR Monel alloy, and Cathaloy alloy. 9. The disk drive suspension assembly according to claim 7, in which said metal comprises one or more of aluminum, gold, chromium and tin. 10. The disk drive suspension assembly according to claim 8, in which said metal is coated on said assembly surface. 11. The disk drive suspension assembly according to claim 8, in which said metal is incorporated into said assembly surface. 12. The disk drive suspension assembly according to claim 2, in which said modifying agent comprises a surface coating formed in situ. 13. The disk drive suspension assembly according to claim 12, in which said coating is vapor deposited. 14. The disk drive suspension assembly according to claim 12, in which said coating is sputter-deposited. 15. The disk drive suspension assembly according to claim 2, in which said modifying agent comprises carbon. 16. The disk drive suspension assembly according to claim 15, in which said carbon comprises carbon black, carbon fiber or a colloidal suspension of graphite. 17. The disk drive suspension assembly according to claim 2, in which said modifying agent comprises an organic composition. 18. The disk drive suspension assembly according to claim 17, in which said organic composition comprises a surfactant. 19. The disk drive suspension assembly according to claim 17, in which said organic composition comprises a synthetic organic polymer. 20. The disk drive suspension assembly according to claim 18, in which said conductor comprises a plurality of conductive traces supported on a plastic film, said plastic film defining said surface and comprising a synthetic organic polymer. 21. A disk drive suspension comprising a signal conductor and a flexure for supporting on said suspension a slider in operating proximity to a disk, said suspension having a surface tending to develop an electrostatic discharge potential, and a surface resistivity modifying agent at said suspension surface electrically coupled to ground and present at said surface in an amount effective for continually leaking charge to ground at a rate greater than the rate of accumulation of electrostatic charge on said assembly surface while avoiding shunting of said conductor said surface resistivity modifying agent being in contact with said conductor. 22. The disk drive suspension according to claim 21, in which said surface resistivity modifying agent comprises an electrostatic potential dissipative composition distributed at said suspension surface in an amount providing said surface with a surface resistivity between about 100,000 ohms per square and 1000 megohms per square. 23. The disk drive suspension according to claim 22, in which said suspension element has a side facing said slider and a side facing away from said slider, said composition being found only on said side facing said slider. 24. The disk drive suspension according to claim 22, in which said composition comprises a metal oxide distributed in or on said surface. 25. The disk drive suspension according to claim 22, in which said composition comprises a metal distributed in or on said surface. 26. The disk drive suspension according to claim 22, in which said composition comprises an organic material distributed in or on said surface. 27. The disk drive suspension according to claim 24, in which said metal oxide comprises chromium oxide, tin oxide, nickel oxide, lead oxide or copper oxide. 28. The disk drive suspension according to claim 25, in which said coating comprises a metal. 29. The disk drive suspension according to claim 28, in which said metal comprises one or more of Silver Barium Beryllium Bismuth Cadmium Mercury Indium Iridium Gold Chromium Nickel Cobalt Tin Aluminum Copper Stainless Steel alloy Iron-Nickel-Chrome alloy Tin-Lead alloy Platinum Tin-Lead-Silver Monel alloy R-Monel alloy K-Monel an alloy Incoloy alloy Inconel alloy 326 Monel alloy KR Monel alloy Cathaloy alloy. 30. The disk drive suspension according to claim 26, in which said composition comprises a surfactant. 31. The disk drive suspension according to claim 26, in which said composition comprises a synthetic organic polymer. 32. The disk drive suspension according to claim 22, in which said composition is incorporated into said surface. 33. The disk drive suspension according to claim 22, in which said composition is coated on said surface. 34. The disk drive suspension according to claim 33, in which said composition comprises one or more of aluminum, gold, chromium and tin. 35. The disk drive suspension according to claim 33, in which said composition is vapor deposited. 36. The disk drive suspension according to claim 33, in which said composition is sputter-deposited. 37. The disk drive suspension according to claim 33, in which said composition comprises carbon. 38. The disk drive suspension according to claim 37, in which said carbon comprises carbon black, carbon fiber or a colloidal suspension of graphite. 39. The disk drive suspension according to claim 33, in which said composition comprises a film-forming organic material. 40. The disk drive suspension according to claim 39, in which said film-forming organic material comprises a surfactant. 41. The disk drive suspension according to claim 33, in which said composition comprises a synthetic organic polymer. 42. A disk drive suspension electrical interconnect comprising a plastic layer, a plurality of conductive traces on a first side of the plastic layers and a metal member on a second side of said plastic layer, and a resistivity modifying agent distributed in or on said first side of said plastic layer and electrically coupled to ground, said agent being present in an amount effective for continually leaking charge to ground at a rate greater than the rate of accumulation of electrostatic charge on said interconnect while avoiding shunting of said conductive traces, said resistivity modifying agent being in contact with said conductive traces. 43. A suspension electrical interconnect comprising plural pairs of conductive traces and an insulative film layer supporting the traces, said film layer having a resistivity tending to build an electrostatic potential on said film layer, and an electrostatic discharge dissipative material disposed on or in said insulative film layer, said material having a lower resistivity than said film layer but higher than will allow shunting of said conductive traces, said material being electrically coupled to ground and present in an amount effective for continually leaking charge to ground at a rate greater than the rate of accumulation of electrostatic charge on said interconnect while avoiding shunting of said traces. 44. The suspension electrical interconnect according to claim 43, in which said traces have a volume resistivity of about 4횞10-8 ohm-cm, said insulative film has a volume resistivity of between about 1횞1011 and 1횞1018 ohm-cm, and said material or said insulative film incorporating said material has a volume resistivity of between about 1횞103 and about 1횞107 ohm-cm. 45. The electrical interconnect according to claim 43, in which said material is disposed on said film layer. 46. The electrical interconnect according to claim 43, in which said material is disposed within said film layer. 47. The electrical interconnect according to claim 43, in which said material comprises a metal oxide. 48. The electrical interconnect according to claim 43, in which said material comprises metal. 49. The electrical interconnect according to claim 43, in which said material comprises carbon. 50. The electrical interconnect according to claim 49, in which said carbon comprises carbon black, carbon fiber or aqueous dispersed graphite. 51. The electrical interconnect according to claim 43, in which said material comprises a film-forming organic composition. 52. The electrical interconnect according to claim 43, in which said film forming organic composition comprises a surfactant. 53. A suspension electrical interconnect, said interconnect comprising a plural pairs of conductive traces, an insulative film layer supporting the traces and supportable by a metal member, said film layer having a resistivity tending to build an electrostatic potential on said film layer, and an electrostatic discharge preventative material disposed on or in said insulative film layer, said material having a lower resistivity than said film layer but higher than will allow shunting of said conductive traces, said material being electrically coupled to ground and present in an amount effective for continually leaking charge to ground at a rate greater than the rate of accumulation of electrostatic charge on said interconnect while avoiding shunting of said conductive traces. 54. The suspension electrical interconnect according to claim 53, in which said traces have a volume resistivity of about 4횞10-6 ohm-cm, said insulative film has a volume resistivity of between about 1횞1011 and 1횞1018 ohm-cm, and said material or said insulative film incorporating said material has a volume resistivity of between about 1횞103 and about 1횞107 ohm-cm. 55. The electrical interconnect according to claim 53, in which said material is disposed on said film layer. 56. The electrical interconnect according to claim 53, in which said material is disposed within said film layer. 57. The electrical interconnect according to claim 53, in which said material comprises a metal oxide. 58. The electrical interconnect according to claim 53, in which said material comprises metal. 59. The electrical interconnect according to claim 53, in which said material comprises carbon. 60. The electrical interconnect according to claim 59, in which said carbon comprises carbon black, carbon fiber or aqueous dispersed graphite. 61. The electrical interconnect according to claim 53, in which said material comprises a film-forming organic composition. 62. The electrical interconnect according to claim 53, in which said film forming organic composition comprises a surfactant. 63. The electrical interconnect according to claim 53, including also a metal member attached to said insulative film layer. 64. A method of reducing electrostatic discharge potential in a disk drive suspension comprising one or more portions tending to build up an electrostatic potential, said one or more portions supporting a signal conductor, the method including exposing at least one surface of a said portion, treating said exposed portion surface with a resistivity modifying agent comprising an electrostatic charge dissipative composition in an amount effective for continually leaking charge to ground at a rate greater than the rate of accumulation of electrostatic charge on said portion surface while avoiding shunting of said conductor and electrically coupling said composition to ground said resistivity modifying agent being in contact with said conductor. 65. The method according to claim 64, including also selecting as said composition a composition having a surface resistivity between about 100,000 ohms per square and 1000 megohms per square. 66. The method according to claim 65, including also selecting as said composition a composition comprising metal oxides, metals, carbon, or organic compositions. 67. A method of preventing electrostatic discharge in a suspension electrical interconnect comprising an insulative film with high resistivity and plural pairs of trace conductors, including disposing a material having a lower resistivity on or in said insulative film in an amount effective for continually leaking charge to ground at a rate greater than the rate of accumulation of electrostatic charge on said interconnect while avoiding shunting of said conductors, and electrically grounding said material said material being in contact with said conductors. 68. A method of reducing electrostatic discharge potential on a disk drive suspension comprising a base portion, a spring portion and a rigid portion adapted to carry a slider, one or more of said portions having a surface tending to build up an electrostatic discharge potential, said one or more portions supporting a signal conductor, the method including treating said surface with an electrostatic discharge dissipative material in an amount effective for continually leaking charge to ground at a rate greater than the rate of accumulation of electrostatic charge on said surface while avoiding shunting of said conductor, and electrically coupling said material to ground said dissipative material being in contact with said conductor. 69. The method according to claim 68, including also selecting as said electrostatic dissipative material a material having a surface resistivity between about 100,000 ohms per square and 1000 ohms per square. 70. The method according to claim 69, including also selecting as said material one or more of metals, metal oxides, carbon, and organic compositions. 71. A disk drive suspension assembly comprising a conductor and a spring element for biasing a slider into operating proximity with a disk, said assembly having a surface tending to develop an electrostatic discharge potential, and a surface resistivity modifying agent at said assembly surface, said agent being present at said assembly surface in an electrostatic discharge potential lowering effective amount, said modifying agent comprising a metal oxide said agent being coupled to ground. 72. The disk drive suspension assembly according to claim 71, in which said metal oxide is coated on said assembly surface. 73. The disk drive suspension assembly according to claim 71, in which said metal oxide is incorporated into said assembly surface. 74. The disk drive suspension assembly according to claim 71, in which said metal oxide comprises chromium oxide, tin oxide, nickel oxide, lead oxide or copper oxide. 75. A disk drive suspension comprising a conductor and a flexure for supporting on said suspension a slider in operating proximity to a disk, said suspension having a surface tending to develop an electrostatic discharge potential, and a surface resistivity modifying agent at said suspension surface in electrostatic discharge potential lowering amount, said surface resistivity modifying agent comprises an electrostatic potential dissipative metal oxide composition distributed in or on said suspension surface in an amount providing said surface with a surface resistivity between about 100,000 ohms per square and 1000 megohms per square. 76. The disk drive suspension according to claim 75, in which said metal oxide comprises chromium oxide, tin oxide, nickel oxide, lead oxide or copper oxide. 77. A suspension electrical interconnect comprising plural pairs of conductive traces and an insulative film layer supporting the traces, said film layer having a resistivity tending to build an electrostatic potential on said film layer, and an electrostatic discharge dissipative metal oxide material disposed on or in said insulative film layer, said material having a lower resistivity than said film layer but higher than will allow shunting of said conductive traces, said material being adapted to be electrically coupled to ground. 78. A suspension electrical interconnect, said interconnect comprising a plural pairs of conductive traces, an insulative film layer supporting the traces and supportable by a metal member, said film layer having a resistivity tending to build an electrostatic potential on said film layer, and an electrostatic discharge preventative metal oxide material disposed on or in said insulative film layer, said material having a lower resistivity than said film layer but higher than will allow shunting of said conductive traces, said material being adapted to be electrically coupled to ground. 79. The disk drive suspension according to claim 78, in which said metal oxide comprises chromium oxide, tin oxide, nickel oxide, lead oxide or copper oxide.