Patent EP0151508A2 successfully refreshed from Google Patents.
EP0151508A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
A flat panel display and a process for its manufacture
Assignee: UK Secretary of State for Defence
•
Filing: 1985-01-04
•
Granted: —
•
Expires: 2005-01-04
Abstract
Abstract A flat panel VDU or TV screen (1) has pixel elements (P) controlled by an array of small single crystal semiconductor bars or chips (9). Power and information are connected directly or capacitatively to the chips (9): chip surfaces have pick-up pads (X', Y', D'). X-Y address lines (X,Y) are provided on a VDU panel substrate (3), and each chip (9) has bridging links (Y'Y') to complete continuity of the Y-line (Y). For data address, data lines (D) are provided on the substrate (3), and decoding and address recognition circuitry is incorporated in each chip (9). Chips (9) may be responsive to more than one address, and may be addressed either singly or a line or block at a time using a single code address. Each chip (9) may control its neighbouring pixels (8). A single crystal wafer (23) Is processed and mounted upon a support (27). Chips (9) are defined by back etching the wafer and separated by stretching the support (27) prior to transfer to a substrate (5). Serf aligned electrodes (X, Y, D) may be produced photolithographically, using shallow angle and overhead illumination. The chips or bars may also be located by means of vacuum chucks.
Inventors
- 👤 John David Benjamin
- 👤 Adrian Leonard Mears
- 👤 John Charles White
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-27 12:31
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/133; G02F1/1333; G02F1/1343; G02F1/1345; G02F1/136
Claims Analysis
Total Claims: 26
Claim 1
Independent Claim
80 words
A flat-panel display of the kind having an electrically responsive optical medium arranged between electrode-bearing substrates, the electrodes being configured to define a multiplicity of pixels, together with a multiplicity of electronic components for controlling the application of drive signals to pixel electrodes corresponding therewith, characterised in that:- the said electronic components are physically separate elements of single-crystal semiconductor material, are located between the electrode-bearing substrates and are arranged with each element coupled to at least one neighbouring pixel electrode.
Claim 2
Dependent Claim
80 words
A flat-panel display of the kind having an electrically responsive optical medium arranged between electrode-bearing substrates, the electrodes being configured to define a multiplicity of pixels, together with a multiplicity of electronic components for controlling the application of drive signals to pixel electrodes corresponding therewith, characterised in that:- the said electronic components are physically separate elements of single-crystal semiconductor material, are located between the electrode-bearing substrates and are arranged with each element coupled to at least one neighbouring pixel electrode.
Claim 3
Dependent Claim
18 words
A display as claimed in claim 1 characterised in that the elements of single crystal material are bars.
Claim 4
Dependent Claim
17 words
A display as claimed in claim 3 characterised in that the elements of single crystal are chips.
Claim 5
Dependent Claim
30 words
A display as claimed in claim 3 characterised in that each chip overlaps and is coupled to a plurality of pixel control electrodes each of which it serves to control.
Claim 6
Dependent Claim
25 words
A display as claimed in any one of the preceding claims characterised in that the elements serve as structural spacers between the electrode bearing substrates.
Claim 7
Dependent Claim
27 words
A display as claimed in any one of the preceding claims characterised in that electrodes of one of the substrates are coupled capacitively to the semiconductor elements.
Claim 8
Dependent Claim
38 words
A display as claimed in any one of the preceding claims, being an X-Y matrix addressed display, characterised in that one of the electrode bearing substrates has pixel control electrodes and also electrodes for X & Y address.
Claim 9
Dependent Claim
27 words
A display as claimed in claim 7 characterised in that it comprises chip elements each including a bridging link to complete continuity of a corresponding address electrode.
Claim 10
Dependent Claim
17 words
A display as claimed in claim 8 characterised in that the bridging link includes a boost amplifier.
Claim 11
Dependent Claim
57 words
A display as claimed in claim 8 or 9 characterised in that each X or Y address electrode is coupled to one row (or column) of chips and also to the next adjacent row (or column) of chips, a bridging link being included in each pair of the adjacent chips to provide an alternative path for continuity.
Claim 12
Dependent Claim
47 words
A display as claimed in any one of the preceding claims 1 to 6, being a data addressed display, characterised in that one of the electrode bearing substrates has pixel control electrodes and also electrodes for data address, and each semiconductor element includes circuitry for address recognition.
Claim 13
Dependent Claim
22 words
A display as claimed in claim 11 characterised in that each element is responsive to a frequency or pulse code modulated address.
Claim 14
Dependent Claim
53 words
A display as claimed in claim 11 or 12 characterised in that each element is a chip responsive to more than a single address, and a plurality of the chips have at least one address in common such that a line, block or pattern of chips can respond simultaneously to a single address.
Claim 15
Dependent Claim
32 words
A display as claimed in any one of the preceding claims 11 to 13 characterised in that it includes coupling between adjacent elements for the transfer of data from element to element.
Claim 16
Dependent Claim
39 words
A display as claimed in any one of the preceding claims 11 to 14 characterised in that each element is a chip, the chips are arranged in rows and each row has an encoder for addressing the chips therein.
Claim 17
Dependent Claim
24 words
A display as claimed in claim 15 characterised in that each row has a pair of encoders, one at each end of the row.
Claim 18
Dependent Claim
28 words
A display as claimed in any one of the preceding claims, characterised in that each element includes duplicate circuits and pick-up electrode pads for performing the same function.
Claim 19
Dependent Claim
37 words
A display as claimed in any one of the preceding claims, characterised in that each element includes circuitry responsive to address signal or to pixel drive signal for extracting power therefrom to operate other circuitry incorporated therein.
Claim 20
Dependent Claim
94 words
A method, for producing the display as claimed in claim 1, characterised in that it includes the following steps:- forming a multiplicity of like circuits in the surface of a semiconductor wafer; forming a passiviation layer over the wafer surface; forming grooves in the wafer to isolate the like circuits, these grooves extending to a depth reaching an etch stop layer buried in the wafer; removing bulk semiconductor material from the reverse side of the wafer; and, removing the etch stop layer to separate the like circuits to form a multiplicity of semiconductor elements.
Claim 21
Dependent Claim
30 words
A method according to claim 19 characterised in that it includes the further step of transferring the separated circuits to a supporting substrate with the aid of a vacuum chuck.
Claim 22
Dependent Claim
19 words
A method according to claim 20 characterised in that the vacuum chuck has a suction surface of perforated silicon.
Claim 23
Dependent Claim
54 words
A method as claimed in claim 19 characterised in that it includes the following additional steps:- prior to separating the like circuits, mounting the wafer face down on an elastomeric support, subsequent to separating the like circuits, stretching the elastomeric support to space out the circuits, and transferring the circuits to a supporting substrate.
Claim 24
Independent Claim
43 words
A method as claimed in any one of claims 19 to 22 characterised in that the circuits are bonded to the supporting substrate by an electrically conductive adhesive agent, the circuits being used as a protective mask during removal of surplus adhesive agent.
Claim 25
Dependent Claim
58 words
A method as claimed in claim 22 characterised in that the surface of the elastomeric support has a mask pattern thereon, the wafer is mounted on the support so that it lies over the mask pattern and the mask pattern is subsequently enlarged with stretching of the elastomeric support for use thereafter as a mask for defining electrodes.
Claim 26
Dependent Claim
102 words
A method as claimed in claim 22 or 24, wherein the transferred circuits are used in defining electrodes aligned therewith, the following steps being performed:- providing a metallised substrate having a photoresist coating; locating the transferred circuits over and in contact with the coated substrate; illuminating the transferred circuits at a shallow angle to form a continuous shadow; inching the transferred circuits sideways; illuminating the transferred circuits a second time to form another continuous shadow; developing the photoresist to define an area corresponding to the area of common shadow; and defining the electrodes using the patterned photoresist as an etch resistant mask.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.