System and method for optically interconnecting memory devices

• US 20040024959A1
• Filed: 08/02/2002
• Published: 02/05/2004
• Est. Priority Date: 08/02/2002
• Status: Active Grant

• Current Assignee: Micron Technology, Inc.
• Original Assignee: Micron Technology, Inc.
• Inventors: Taylor, George R.
• Granted Patent: US 7,200,024 B2
• Time in Patent Office: Days
• US Class Current: 711/105
• CPC Class Codes: G11C 5/06 Arrangements for interconnecting storage elements electrically, e.g. by wiring
• CPC Class Codes: G11C 5/063 Voltage and signal distribution in integrated semi-conductor memory access lines, e.g. word-line, bit-line, cross-over resistance, propagation delay
• CPC Class Codes: G11C 7/02 with means for avoiding parasitic signals
• CPC Class Codes: G11C 7/1006 Data managing, e.g. manipulating data before writing or reading out, data bus switches or control circuits therefor
• CPC Class Codes: G11C 7/1051 Data output circuits, e.g. read-out amplifiers, data output buffers, data output registers, data output level conversion circuits
• CPC Class Codes: G11C 7/1054 Optical output buffers
• CPC Class Codes: G11C 7/1069 I/O lines read out arrangements
• CPC Class Codes: G11C 7/1078 Data input circuits, e.g. write amplifiers, data input buffers, data input registers, data input level conversion circuits
• CPC Class Codes: G11C 7/1081 Optical input buffers
• CPC Class Codes: G11C 7/1096 Write circuits, e.g. I/O line write drivers
• CPC Class Codes: H01L 2224/0401 Bonding areas specifically adapted for bump connectors, e.g. under bump metallisation [UBM]
• CPC Class Codes: H01L 2224/16 of an individual bump connector
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/01055 Cesium [Cs]
• CPC Class Codes: H01L 2924/3025 Electromagnetic shielding

Abstract

A memory device includes a semiconductor substrate in which memory circuitry has been fabricated. An address converter and a control signal converter are coupled to an address decoder and control logic, respectively. The address and control converters are operable to receive and convert optical address and control signals, respectively, into corresponding electrical address signals applied to the address decoder and control signals applied to the control logic. A read/write circuit on the substrate is coupled to a data converter formed in the substrate. The data converter is operable to receive and convert optical write data signals into corresponding electrical data signals to be applied to the read/write circuit and to receive and convert electrical read data signals into corresponding optical read data signals.

Claims

1. A memory device, comprising:

a semiconductor substrate;

an address converter fabricated in the substrate, the address converter being operable to receive and convert optical address signals into corresponding electrical address signals;

an address decoder fabricated in the semiconductor substrate, the address decoder being coupled to the address converter to receive the electrical address signals from the address converter;

a data converter fabricated in the substrate, the data converter being operable to receive and convert optical write data signals into corresponding electrical write data signals and to receive and convert electrical read data signals into corresponding optical read data signals;

a read/write circuit fabricated in the semiconductor substrate, the read/write circuit being coupled to the data converter to receive the electrical read data signals from the data converter and to couple the electrical write data signals to the data converter;

a control signal converter fabricated in the substrate, the control signal converter being operable to receive and convert optical control signals into corresponding electrical control signals;

a control logic unit fabricated in the semiconductor substrate, the control logic unit being coupled to a control converter fabricated in the substrate; and

a memory-cell array fabricated in the semiconductor substrate, the memory-cell array being coupled to the address decoder, control circuit, and read/write circuit.

2. The memory device of claim 1 wherein the memory device comprises a dynamic random access memory.

3. The device of claim 1 wherein the optical control signals comprise clock enable signals, row address strobe signals, column address strobe signals, write enable signals and chip select signals.

4. The device of claim 1 wherein the data converter comprises a plurality of optical transmitters and receivers fabricated in the substrate.

5. The device of claim 1 wherein the control signal converter and address converter each comprise a plurality of optical receivers fabricated in the substrate.

6. The device of claim 1 wherein the data converter comprises a cavity type laser operable to transmit optical signals.

7. The device of claim 1 wherein the control signal, address and data converters comprise optical Darlington transistors.

8. The device of claim 1 wherein the control signal, address and data converters comprise optical field effect transistors operable to receive optical signals.

9. A memory module, comprising:

an insulative substrate;

a plurality of memory devices mounted on the substrate, each memory device comprising;

a semiconductor substrate;

a plurality of electrical input and output terminals fabricated in the semiconductor substrate including electrical data terminals operable to output read data signals and input write data signals, and electrical address and control terminals operable to input address and control signals;

a plurality of optical receivers fabricated in the semiconductor substrate coupled to corresponding data, control and address terminals, the receivers being operable to receive optical signals and translate the optical signals into corresponding electrical signals;

a plurality of optical transmitters fabricated in the semiconductor substrate coupled to corresponding data terminals, the optical transmitters being operable to receive read data signals and translate the read data signals into corresponding optical read data signals; and

a plurality of optical paths coupled to the optical receivers and transmitters.

10. The memory module of claim 9 wherein the plurality of optical transmitters are operable to transmit signal packets corresponding to electrical signals input to the optical transmitters.

11. The memory module of claim 9 wherein the control signals comprise clock enable signals, row address strobe signals, column address strobe signals, write enable signals and chip select signals.

12. The memory module of claim 9 wherein the memory devices comprise dynamic random access memories.

13. The memory module of claim 9 wherein the optical receivers comprises cavity type lasers operable to transmit optical signals.

14. The memory module of claim 9 wherein the optical paths are fabricated in the insulative substrate.

15. The memory module of claim 9 wherein the optical receivers comprise optical Darlington transistors.

16. The memory module of claim 9 wherein the optical receivers comprise optical field effect transistors operable to receive optical signals.

17. The memory module of claim 9 wherein each optical path comprises a plurality of optical links.

18. The memory module of claim 9 wherein each optical path comprises a fiber optic link.

19. The memory module of claim 9 wherein each optical path comprises free space.

20. The memory module of claim 9 wherein the optical paths comprise control, address and data busses.

21. The memory module of claim 9 wherein the insulative substrate comprises a plurality of optical paths embedded within the insulative substrate.

22. A memory module, comprising:

an insulative substrate;

a plurality of memory devices mounted on the substrate, each memory device comprising;

a semiconductor substrate;

a plurality of electrical input and output signal lines fabricated in the semiconductor substrate including electrical data signal lines operable to output electrical read data signals and input electrical write data signals, and electrical address and control signal lines operable to input electrical address and control signals;

a plurality of optical receivers fabricated in the semiconductor substrate coupled to corresponding data, control and address signal lines, the receivers being operable to receive optical signals and develop corresponding electrical signals; and

a plurality of optical transmitters fabricated in the semiconductor substrate coupled to corresponding data signal lines, the optical transmitters being operable to receive electrical read data signals and develop corresponding optical read data signals;

a memory hub mounted on the insulative substrate, the memory hub having an input/output port and a plurality of input and output terminals including terminals outputting optical write data signals, terminals inputting optical read data signals, and terminals outputting optical command and address signals, the memory hub being operable to receive input signals coupled to the input/output port and to apply corresponding optical signals to the terminals of the memory hub, the memory hub being further operable to receive optical signals at the terminals of the memory hub and to apply output signals to the input/output port; and

a plurality of optical paths coupling the terminals of the memory hub to the optical transmitters and receivers of the memory devices.

23. The memory module of claim 22 wherein the input/output port is operable to receive optical input signals, and transmit optical output signals.

24. The memory module of claim 23 wherein the optical input signals, comprise control, address and write data signals, and the optical output signals comprise read data signals.

25. The memory module of claim 22 wherein the input/output port is operable to receive electrical input signals, and transmit electrical output signals.

26. The memory module of claim 25 wherein the electrical input signals, comprise control, address and write data signals, and the electrical output signals comprise read data signals.

27. The memory module of claim 22 wherein the memory devices comprise dynamic random access memory devices.

28. The memory module of claim 22 wherein the optical transmitters comprise cavity type lasers operable to transmit optical signals.

29. The memory module of claim 22 wherein the optical receivers comprise optical Darlington transistors.

30. The memory module of claim 22 wherein the optical receivers comprise optical field effect transistors operable to receive optical signals.

31. The memory module of claim 22 wherein each optical path comprises a plurality of optical links.

32. The memory module of claim 22 wherein each optical path comprises a fiber optic link.

33. The memory module of claim 22 wherein each optical path comprises free space.

34. The memory module of claim 22 wherein each optical path comprises control, address and data busses.

35. The memory module of claim 22 wherein the optical paths are fabricated in the insulative substrate.

36. The memory module of claim 22 wherein the memory hub applies optical hub control, address and data signals to each memory device on the module simultaneously.

37. The memory module of claim 22 wherein the memory hub detects device address information in the input signal and applies optical control, address and data signals to a corresponding memory device on the module.

38. The memory module of claim 22 wherein the insulative substrate comprises a plurality of optical paths embedded within the insulative substrate.

39. A memory module, comprising:

an insulative substrate;

a plurality of memory devices mounted on the substrate, each memory device comprising;

a semiconductor substrate; and

a plurality of electrical input and output signal lines fabricated on the semiconductor substrate including electrical data signal lines operable to output electrical read data signals and input electrical write data signals, and electrical address and control signal lines operable to input electrical address and control signals;

a memory hub mounted on the insulative substrate, the memory hub having an optical input/output port and a plurality of electrical input and output terminals including terminals outputting electrical write data signals, terminals inputting electrical read data signals, and terminals outputting electrical command and address signals, the memory hub being operable to receive optical input signals coupled to the input/output port and to apply corresponding electrical signals to the terminals of the memory hub, the memory hub being further operable to receive electrical signals at the terminals of the memory hub and to apply optical output signals to the input/output port; and

a plurality of signal paths coupling the terminals of the memory hub to the data, address and control signal lines on the memory devices.

40. The memory module of claim 39 wherein the optical input signals, comprise optical control, address and write data signals, and the optical output signals comprise optical read data signals.

41. The memory module of claim 39 wherein the memory devices comprise dynamic random access memory devices.

42. The memory module of claim 39 wherein each signal path comprises a plurality of conductive traces.

43. The memory module of claim 39 wherein each signal path comprises control, address and data busses.

44. The memory module of claim 39 wherein the memory hub is operable to apply electrical hub control, address and data signals to each memory device on the module simultaneously.

45. The memory module of claim 39 wherein the memory hub is operable to detect device address information in the input signal and apply electrical control, address and data signals to a corresponding memory device on the module.

46. The memory module of claim 39 wherein the insulative substrate comprises a plurality of optical paths embedded within the insulative substrate, and further wherein at least one optical path is coupled to the optical input/output port.

47. A memory module, comprising:

an insulative substrate having a plurality of optical paths extending therethrough;

a plurality of memory devices mounted on the substrate, each memory device comprising;

a semiconductor substrate;

a plurality of electrical input and output signal lines fabricated in the semiconductor substrate including electrical data signal lines operable to output electrical read data signals and input electrical write data signals, and electrical address and control signal lines operable to input electrical address and control signals;

a plurality of optical receivers fabricated in the semiconductor substrate operably coupling the optical paths in the insulative substrate with corresponding data, control and address signal lines, the receivers being operable to receive optical signals and generate corresponding electrical signals;

a plurality of optical transmitters fabricated in the semiconductor substrate operably coupling the optical paths in the insulative substrate with corresponding data signal lines, the optical transmitters being operable to receive electrical read data signals and generate corresponding optical read data signals; and

a memory hub mounted on the insulative substrate, the memory hub having an input/output port and a plurality of optical input terminals and optical output terminals including terminals outputting optical write data signals, terminals inputting optical read data signals, and terminals outputting optical command and address signals, the terminals being coupled to corresponding optical paths in the substrate and being operable to transmit the optical command address and write data signals to the optical receivers in the memory devices, the terminals being further operative to receive the optical read data signals from the optical transmitters in the memory devices, the memory hub being operable to receive optical input signals coupled to the input/output port and to apply corresponding optical signals to the terminals of the memory hub, the memory hub being further operable to receive optical signals at the terminals of the memory hub and to apply optical output signals to the input/output port.

48. The memory module of claim 47 wherein the optical input signals, comprise control, address and write data signals, and the optical output signals comprise read data signals.

49. The memory module of claim 47 wherein the memory devices comprise dynamic random access memory devices.

50. The memory module of claim 47 wherein the optical transmitters comprise cavity type lasers operable to transmit optical signals.

51. The memory module of claim 47 wherein the optical receivers comprise optical Darlington transistors.

52. The memory module of claim 47 wherein the optical receivers comprise optical field effect transistors operable to receive optical signals.

53. The memory module of claim 47 wherein each optical path comprises a plurality of optical links.

54. The memory module of claim 47 wherein each optical path comprises a fiber optic link.

55. The memory module of claim 47 wherein each optical path comprises free space.

56. The memory module of claim 47 wherein each optical path comprises control, address and data busses.

57. The memory module of claim 47 wherein the memory hub is operable to appy optical hub control, address and data signals to each memory device on the module simultaneously.

58. The memory module of claim 47 wherein the memory hub is operable to detect device address information in the optical input signal coupled to the input/output port and apply optical control, address and data signals to a corresponding memory device on the module.

59. A computer system, comprising:

a data input device;

a data output device;

a processor coupled to the data input and data output devices;

a insulative substrate;

a controller coupled to the substrate and electrically coupled to the processor, the controller being operable to receive optical data signals and apply optical control, address and data signals to an optical path at a controller port;

a plurality of memory devices mounted on the substrate, each memory device comprising;

a semiconductor substrate;

a plurality of electrical input and output signal lines fabricated in the semiconductor substrate including electrical data signal lines operable to output electrical read data signals and input electrical write data signals; and

electrical address and control signal lines operable to input electrical address and control signals;

a plurality of optical receivers fabricated in the semiconductor substrate coupled to corresponding data, control and address signal lines, the receivers being operable to receive optical signals and generate corresponding electrical signals; and

a plurality of optical transmitters fabricated in the semiconductor substrate coupled to corresponding data signal lines, the optical transmitters being operable to receive electrical read data signals and generate corresponding optical read data signals;

a memory hub mounted on the insulative substrate, the memory hub having an input/output port and a plurality of input and output terminals including terminals outputting optical write data signals, command signals and address signals, and terminals inputting optical read data signals, the memory hub being operable to receive input signals coupled to the input/output port and to apply corresponding optical signals to the terminals of the memory hub, the memory hub being further operable to receive optical signals at the terminals of the memory hub and to apply output signals to the input/output port; and

a plurality of optical paths coupling the terminals of the memory hub to the optical transmitters and receivers of the memory devices.

60. The computer system of claim 59 wherein the optical paths are embedded within the insulative substrate.

61. The computer system of claim 59 wherein the input/output port is operable to receive optical input signals, and transmit optical output signals.

62. The computer system of claim 61 wherein the optical input signals, comprise control, address and write data signals, and the optical output signals comprise read data signals.

63. The computer system of claim 59 wherein the input/output port is operable to receive electrical input signals, and transmit electrical output signals.

64. The computer system of claim 63 wherein the electrical input signals, comprise control, address and write data signals, and the electrical output signals comprise read data signals.

65. The computer system of claim 59 wherein the memory devices comprise dynamic random access memory devices.

66. The computer system of claim 59 wherein the optical transmitters comprise cavity type lasers operable to transmit optical signals.

67. The computer system of claim 59 wherein the optical receivers comprise optical Darlington transistors.

68. The computer system of claim 59 wherein the optical receivers comprise optical field effect transistors operable to receive optical signals.

69. The computer system of claim 59 wherein each optical path comprises a plurality of optical links.

70. The computer system of claim 59 wherein each optical path comprises a fiber optic link.

71. The computer system of claim 59 wherein each optical path comprises free space.

72. The computer system of claim 59 wherein each optical path comprises control, address and data busses.

73. The computer system of claim 59 wherein the memory hub is operable to apply optical hub control, address and data signals to each memory device on the module simultaneously.

74. The computer system of claim 59 wherein the memory hub is operable to detect device address information in the input signal and apply optical control, address and data signals to a corresponding memory device on the module.

75. A method of communicating control and address signals to and/or from a memory device, comprising:

coupling optical signals corresponding to control and address signals to the memory device;

receiving the optical control and address signals in the memory device;

developing electrical control and address signals on the memory device corresponding to the optical control and address signals; and

accessing a memory location within the memory device in accordance with the control and address signals.

76. The method of claim 75, further comprising:

coupling optical write data signals corresponding to write data signals to the memory device;

receiving the optical write data signals in the memory device;

developing electrical write data signals on the memory device corresponding to the optical write data signals; and

writing data to the memory location.

77. The method of claim 75, further comprising:

reading data from a memory location;

developing optical read data signals on the memory device corresponding to the optical read data; and

coupling the optical read data signals from the memory device.

78. The method of claim 75 wherein the act of coupling optical signals corresponding to control and address signals to the memory device comprises coupling control and address signals over at least one optical fiber.

79. The method of claim 75 wherein the acts of coupling optical signals corresponding to control and address signals to the memory device comprises coupling control and address signals over free space.

80. The method of claim 75 wherein the act of coupling optical signals corresponding to control and addresses signals to the memory device comprises coupling optical signals corresponding to the control and address signals to the device over an optical path embedded in a substrate.

81. The method of claim 80 wherein the act of coupling optical signals corresponding to control, address and write data signals to the memory device over an optical path in a substrate comprise coupling control, address and data signals over at least one optical fiber embedded in the substrate.

82. The method of claim 75 wherein the act of coupling optical signals to the memory device comprises coupling optical signals to the memory device in the form of optical signal packets.

83. A method of communicating control and address signals to a memory device, comprising:

coupling optical signals corresponding to control and address signals from a memory hub to the memory device;

receiving the optical control and address signals in the memory device;

developing electrical control and address signals in the memory device corresponding to the optical control and address signals; and

accessing a memory location within the memory device in accordance with the control and address signals.

84. The method of claim 83, further comprising:

coupling optical write data signals corresponding to write data signals from the memory hub to the memory device;

receiving the optical write data signals in the memory device;

developing electrical write data signals on the memory device corresponding to the optical write data signals; and

writing data to the memory location.

85. The method of claim 83, further comprising:

reading data from a memory location;

developing optical read data signals on the memory device corresponding to the optical read data; and

coupling the optical read data signals from the memory device to the memory hub.

86. The method of claim 83 wherein the act of coupling optical signals corresponding to control and address signals to the memory device comprises coupling control and address signals over at least one optical fiber.

87. The method of claim 83 wherein the act of coupling optical signals corresponding to control and address signals to the memory device comprises coupling control and address signals over free space.

88. The method of claim 83 wherein the act of coupling optical signals corresponding to control and address signals to the memory device further comprises coupling optical signals corresponding to the control and address signals to the hub over an optical path in a substrate.

89. The method of claim 88 further comprising coupling optical control and address signals from a controller to the hub over an optical path.

90. The method of claim 89 wherein the act of coupling optical control and address signals from a controller to the hub over an optical path comprises coupling optical signals between the hub and controller in the form of optical signal packets.

91. The method of claim 88 wherein the acts of coupling optical signals corresponding to control and address signals to the hub over an optical path in a substrate comprise coupling control and address over at least one optical fiber.

92. The method of claim 83 wherein the act of coupling optical signals between the memory hub and the memory device comprises coupling optical signals to and from the memory device in the form of optical signal packets.