Single crystal silicon arrayed devices with optical shield between transistor and substrate

• US 6,317,175 B1
• Filed: 06/06/1995
• Issued: 11/13/2001
• Est. Priority Date: 12/31/1990
• Status: Expired due to Term

• Current Assignee: Kopin Corporation
• Original Assignee: Kopin Corporation
• Inventors: Salerno, Jack P., Zavracky, Paul M., Spitzer, Mark B., Dingle, Brenda
• Primary Examiner(s): Parker, Kenneth
• Application Number:
  US08/471,575
• Time in Patent Office: 2,352 Days
• Field of Search: 349/45, 349/44, 349/110, 349/111, 437/209, 437/974, 117/43, 117/47
• US Class Current: 349/45
• CPC Class Codes: A61B 3/113 for determining or recording eye movement
• CPC Class Codes: G02B 2027/0132 comprising binocular systems
• CPC Class Codes: G02B 2027/0138 comprising image capture systems, e.g. camera
• CPC Class Codes: G02B 2027/0187 slaved to motion of at least a part of the body of the user, e.g. head, eye
• CPC Class Codes: G02B 2027/0198 System for aligning or maintaining alignment of an image in a predetermined direction
• CPC Class Codes: G02B 27/0093 with means for monitoring data relating to the user, e.g. head-tracking, eye-tracking
• CPC Class Codes: G02B 27/017 Head mounted
• CPC Class Codes: G02B 27/0172 characterised by optical features
• CPC Class Codes: G02B 5/30 Polarising elements light-modulating devices with active elements G02F1/00
• CPC Class Codes: G02F 1/13613 the semiconductor element being formed on a first substrate and thereafter transferred to the final cell substrate
• CPC Class Codes: G03B 21/10 Projectors with built-in or built-on screen
• CPC Class Codes: G03B 21/28 Reflectors in projection beam in illumination beam G03B21/2066
• CPC Class Codes: G03B 33/12 using beam-splitting or beam-combining systems, e.g. dichroic mirrors
• CPC Class Codes: G03B 37/04 with cameras or projectors providing touching or overlapping fields of view
• CPC Class Codes: G09G 2300/023 Display panel composed of stacked panels
• CPC Class Codes: G09G 2300/0809 Several active elements per pixel in active matrix panels
• CPC Class Codes: G09G 2300/0842 forming a memory circuit, e.g. a dynamic memory with one capacitor
• CPC Class Codes: G09G 2320/0233 Improving the luminance or brightness uniformity across the screen
• CPC Class Codes: G09G 2320/041 Temperature compensation
• CPC Class Codes: G09G 2320/043 Preventing or counteracting the effects of ageing
• CPC Class Codes: G09G 2340/0464 : Positioning
• CPC Class Codes: G09G 2370/042 : for monitor identification
• CPC Class Codes: G09G 3/30 : using electroluminescent panels
• CPC Class Codes: G09G 3/36 : using liquid crystals
• CPC Class Codes: G09G 3/3607 : for displaying colours or for displaying grey scales with a specific pixel layout, e.g. using sub-pixels display of colours in flat matrix panels other than liquid crystal displays G09G3/2003; grey scales specific for television H04N3/127
• CPC Class Codes: G09G 3/3614 : Control of polarity reversal in general
• CPC Class Codes: G09G 3/3648 : using an active matrix G09G3/367 - G09G3/3696 take precedence
• CPC Class Codes: H01L 21/8221 : Three dimensional integrated circuits stacked in different levels
• CPC Class Codes: H01L 2221/68359 : used as a support during manufacture of interconnect decals or build up layers
• CPC Class Codes: H01L 2221/68363 : used in a transfer process involving transfer directly from an origin substrate to a target substrate without use of an intermediate handle substrate
• CPC Class Codes: H01L 25/0756 : Stacked arrangements of devices
• CPC Class Codes: H01L 25/50 : Multistep manufacturing processes of assemblies consisting of devices, each device being of a type provided for in group H01L27/00 or H01L29/00 H01L21/50 takes precedence
• CPC Class Codes: H01L 27/0688 : Integrated circuits having a three-dimensional layout
• CPC Class Codes: H01L 27/1214 : comprising a plurality of TFTs formed on a non-semiconducting substrate, e.g. driving circuits for AMLCDs
• CPC Class Codes: H01L 27/1266 : the substrate on which the devices are formed not being the final device substrate, e.g. using a temporary substrate
• CPC Class Codes: H01L 27/1274 : using crystallisation of amorphous semiconductor or recrystallisation of crystalline semiconductor
• CPC Class Codes: H01L 27/156 : two-dimensional arrays
• CPC Class Codes: H01L 29/786 : Thin film transistors, i.e. transistors with a channel being at least partly a thin film transistors having only the source or the drain region on an insulator layer H01L29/0653; thin film FinFETs H01L29/785
• CPC Class Codes: H01L 29/78603 : characterised by the insulating substrate or support H01L29/78657 takes precedence
• CPC Class Codes: H01L 29/78648 : arranged on opposing sides of the channel
• CPC Class Codes: H01L 2924/00 : Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 : Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01L 2924/09701 : Low temperature co-fired ceramic [LTCC]
• CPC Class Codes: H01L 33/0062 : for devices with an active region comprising only III-V compounds
• CPC Class Codes: H01S 5/423 : having a vertical cavity
• CPC Class Codes: H04N 5/70 : Circuit details for electroluminescent devices
• CPC Class Codes: H04N 5/74 : Projection arrangements for image reproduction, e.g. using eidophor
• CPC Class Codes: H04N 5/7441 : the modulator being an array of liquid crystal cells
• CPC Class Codes: H04N 5/7491 : of head mounted projectors
• CPC Class Codes: H04N 9/3108 : by using a single electronic spatial light modulator
• CPC Class Codes: H04N 9/312 : Driving therefor driving of electronic spatial light modulators in displays other than projection devices G09G3/34, G09G3/36; control of liquid crystal elements G02F1/133; control of micromechanical modulators G02B26/08
• CPC Class Codes: H04N 9/3141 : Constructional details thereof details not peculiar to the presence of an electronic spatial light modulator G03B21/14
• CPC Class Codes: H04N 9/3173 : wherein the projection device is specially adapted for enhanced portability
• CPC Class Codes: H05B 33/12 : Light sources with substantially two-dimensional radiating surfaces

Abstract

A display panel is formed using a single crystal thin-film transistors that are transferred to substrates for display fabrication. Pixel arrays form light valves or switches that can be fabricated with control electronics in the thin-film material prior to transfer. The resulting circuit panel is then incorporated into a projection display system with a light emitting or liquid crystal material to provide the desired light valve.

Claims

1. A projection display device comprising:

an optically transmissive substrate positioned to receive light from a light source;

a light valve matrix secured to the substrate and comprising an array of transistors formed from a thin film of single crystal material, an array of electrodes, each electrode being electrically connected to a transistor, a gate positioned between a channel region of each transistor and the optically submissive substrate, a light transmitting material through which light from the light source is selectively transmitted, and an array of optical shields positioned between the gate of each transistor and the optically transmissive substrate to inhibit transmission of light from the light source to the transistors;

a driver circuit electrically connected to the light valve matrix for actuating the light valves; and

an optical system for projecting light transmitted through actuated light valves onto a viewing surface.

2. The projection display device of claim 1 wherein the light valve matrix is secured to the substrate with an adhesive.

3. The projection display device of claim 1 wherein each light valve comprises at least one transistor, an electrode and a respective volume of the light transmitting material.

4. The projection display device of claim 1 wherein the transistor array and the electrode array are formed in a thin film of substantially single crystal silicon material.

5. The projection display device of claim 1 further comprising a sealed cavity in which the light transmitting material is retained adjacent to the thin film of single crystal material.

6. The projection display device of claim 1 wherein the driver circuit is formed in or on the thin film of single crystal material, the driver circuit being electrically connected to each of the transistors such that the driver circuit is capable of selectively actuating a plurality of transistors, the electrodes being connected to the actuated transistors for producing an electric field in the light transmitting material.

7. The projection display device of claim 1 wherein the transistor array and the electrode array are arranged as a light valve array comprising a plurality of columns and rows, the driver circuit comprising a first circuit electrically connected to each column of the light valve array, and a second circuit electrically connected to each row of the light valve array.

8. The projection display device of claim 1 wherein the light valve matrix is attached to the optically transmissive substrate with an adhesive.

9. The projection display device of claim 1 further comprising additional light valve matrices, each light valve matrix adapted to selectively transmit light of a primary color.

10. The projection display device of claim 9 wherein the optical system further comprises a dichroic prism for combining the primary color light transmitted by each matrix into a multi-color light image.

11. The projection display device of claim 1 wherein the viewing surface is a reflective surface such that light is directed from the reflective surface to a viewing screen.

12. The projection display device of claim 1 wherein the display is adapted to be used in a projection monitor.

13. The projection display device of claim 1 wherein the display is adapted to be used in a high resolution monitor system.

14. The projection display device of claim 1 wherein the light transmitting material is liquid crystal.

15. The projection display device of claim 1 wherein the optical shields are positioned between the gate of each transistor and the optically transmissive substrate.

16. The projection display device of claim 1 wherein the optical shields are disposed between the transistors and the light transmitting material.

17. The projection display device of claim 1 wherein the optical shields include a first optical shield array positioned between the transistors and the optically transmissive substrate and a second optical shield array positioned between the transistors and the light transmitting material.

19. The projection display device of claim 16 wherein the single crystal silicon material comprises essentially single crystal silicon.

18. A projection display device comprising:

a light source;

an optically transmissive substrate positioned to receive light from the light source;

a light valve matrix secured to the substrate with an adhesive and being comprised of an array of transistors formed from a thin film of single crystal silicon material, a gate positioned between a channel region of each transistor and the optically transmissive substrate, an array of electrodes, each electrode being electrically connected to a transistor, a light transmitting material positioned adjacent to the single crystal material such that an electric field applied to the light transmitting material alters a light transmitting property thereof to allow light from the light source to be transmitted through the light transmitting material, and an array of optical shields positioned between the gate of each transistor and the substrate to inhibit transmission of light from the light source to the transistors;

a driver circuit formed in the thin film of single crystal silicon material, the driver circuit being electrically connected to the light valve matrix to selectively actuate the light valves; and

an optical system for projecting light transmitted through actuated light valves onto an enlarged viewing surface.

20. The projection display device of claim 18 wherein each light valve comprises at least one transistor, an electrode and a respective volume of the light transmitting material.

21. The projection display device of claim 18 further comprising additional light valve matrices, each light valve matrix adapted to selectively transmit light of a primary color.

22. The projection display device of claim 21 wherein the optical system further comprises a dichroic prism for combining the primary color light transmitted by each matrix into a multi-color light image.

23. The projection display device of claim 18 wherein the enlarged viewing surface is a reflective surface such that light is directed from the reflective surface to a viewing screen.

24. The projection display device of claim 18 wherein the display is adapted to be used in a projection monitor.

25. The projection display device of claim 18 wherein the display is adapted to be used in a high resolution monitor system.

26. The projection display device of claim 18 wherein the light transmitting material is liquid crystal.

27. The projection display device of claim 18 wherein the optical shields are positioned between the gate of each transistor and the optically tansmissive substrate.

28. The projection display device of claim 18 wherein the optical shields are disposed between the transistors and the light transmitting material.

29. The projection display device of claim 18 wherein the optical shields include a first optical shield array positioned between the transistors and the optically transmissive substrate and a second optical shield array positioned between the transistors and the light transmitting material.

30. A projection display device comprising:

a back-light source;

an optically transmissive substrate positioned to receive light from the back-light source;

a light valve matrix secured to the substrate and comprising an array of transistors formed from a thin film of single crystal material, each transistor having a channel and a gate positioned between the channel and the optically transmissive substrate, an array of electrodes each electrode being electrically connected to a transistor, a light transmitting material through which light from the back-light source is selectively transmitted, and a first optical shield positioned between each transistor and the light transmitting material;

a second optical shield positioned between the gate of each transistor and the optically transmissive substrate;

a driver circuit electrically connected to the light valve matrix for actuating the light valves; and

an optical system for projecting light transmitted through actuated light valves onto a viewing surface.

31. The projection display device of claim 30 wherein the transistor array is secured to the optically transmissive substrate with an epoxy.

32. The projection display device of claim 30 wherein each light shield comprises a metal.

33. The projection display device of claim 30 further comprising a substantially planar boundary between the array of transistors and the light transmitting material.

34. A liquid crystal-display device comprising:

a light source;

a liquid crystal display device having an active matrix circuit over a substrate, the active matrix circuit comprising a plurality of pixels including an array of transistors formed from a single crystal material, each transistor having a gate positioned between the single crystal material and the substrate, and an array of pixel electrodes, each electrode being electrically connected to a transistor, the array of pixel electrodes having an active area with a diagonal array dimension no greater than 42 millimeters, the pixel electrodes are formed in lines and there are at least 800 lines per inch such that each pixel has a pixel size of 31.8 microns or less, and an array of optical shields positioned between the array of transistors and the substrate and registered to the transistors to inhibit transmission of light from the light source to the transistors;

a driver circuit electrically connected to the active matrix circuit that actuates the active matrix; and

an optical system to magnify an image on the display device.

35. The display of claim 34 wherein the diagonal array dimension is no greater than 21 millimeters.

36. The display of claim 34 where there is at least 1200 lines per inch.

37. The display of claim 34 wherein the array of pixel electrodes has at least 750,000 pixel electrodes.

38. A display device comprising:

a backlight source;

a light valve device having a light valve matrix secured to a substrate, the substrate being optically transmissive and positioned to receive light from the backlight source;

the light valve matrix comprising a plurality of pixels including an array of transistors formed from a thin film of single crystal material, each transistor having a gate positioned between the single crystal material and the substrate, and an array of pixel electrodes, each electrode being electrically connected to a transistor, the array of pixel electrodes having an active area with a diagonal array dimension of less than 42 millimeters, the array of pixel electrodes being optically coupled to a light transmitting material through which light from the backlight source is selectively transmitted, the pixels being formed in lines such that there are at least 800 lines per inch and each pixel has a size of 31.8 microns or less and an array of optical shields positioned between the array of transistors and the substrate and registered to the transistors to inhibit transmission of light from the backlight source to the transistors;

a driver circuit electrically connected to the light valve matrix for actuating the light valves; and

an optical system to magnify the image on the light valve device.

39. The display of claim 38 wherein the light valve device further comprises a counterelectrode and liquid crystal and the array of transistors are in a first plane, and the counterelectrode extending in a second plane that is parallel to the first plane, and the liquid crystal layer interposed in a cavity between the two planes, the cavity having no spacers in the active area.

40. The display of claim 38 wherein the pixel electrodes are formed in lines and there are at least 800 lines per inch.

41. The display of claim 40 where there is at least 1000 lines per inch.

42. The display of claim 41 where there is at least 1200 lines per inch.

43. The display of claim 42 wherein there is approximately 2000 lines per inch.

44. The display of claim 38 wherein the array of pixel electrodes has at least 750,000 pixel electrodes.

45. The display of claim 38 wherein the diagonal array dimension is no greater than 21 millimeters.

46. The display of claim 45 wherein the diagonal array dimension is no greater than 16.26 millimeters.

47. The device of claim 38 wherein the array of optical shields is disposed between an optically transmissive substrate and a source and drain region of each transistor.