Device for encapsulating and passivating a circuit for flat screens

• US 5,606,194 A
• Filed: 02/10/1995
• Issued: 02/25/1997
• Est. Priority Date: 06/26/1992
• Status: Expired due to Term

• Current Assignee: Thomson-Lcd
• Original Assignee: Thomson-Lcd
• Inventors: Lebrun, Hugues, Mulatier, Laurence
• Primary Examiner(s): Saadat, Mahshid D.
• Assistant Examiner(s): CLARK, SHEILA V
• Application Number:
  US08/351,408
• Time in Patent Office: 746 Days
• Field of Search: 257/432, 257/433, 257/434, 257/202, 257/678, 257/98, 257/99, 359/67, 359/59
• US Class Current: 257/433
• CPC Class Codes: G02F 1/133512 Light shielding layers, e.g. black matrix G02F1/136209 takes precedence
• CPC Class Codes: G02F 1/1339 Gaskets; Spacers; Sealing of cells
• CPC Class Codes: G02F 1/13454 Drivers integrated on the active matrix substrate G02F1/136277 takes precedence

Abstract

A device for encapsulating and passivating integrated control circuits of flat screens. A sealing bead is placed on a substrate plate in order to encapsulate and passivate an integrated control circuit mounted on the plate. In one embodiment, the sealing bead is placed directly on top of the control circuit. In a second embodiment, the sealing bead is placed on both sides of the circuit so as to form a chamber which is separate from that which contains the active matrix. In a third embodiment, an opaque material is also placed on top of the circuit which acts as a spacer and may also act as a "black matrix".

Claims

1. Device for encapsulating and passivating electronic circuits, comprising:

a substrate plate;

an electronic circuit mounted on said substrate plate;

an active matrix mounted on said substrate plate; and

a sealing bead deposited on said substrate plate and surrounding said electronic circuit so as to form a sealed enclosure separate from said active matrix.

5. Device for encapsulating and passivating electronic circuits according to one of claims 4 and 1-3, characterized in that the electronic circuit is an integrated addressing circuit of an active matrix of a liquid-crystal or plasma screen.

6. Device for encapsulating and passivating electronic circuits according to one of claims 4 and 1-3, characterized in that the substrate plate on which the electronic circuits are produced is made of transparent material.

7. Device for encapsulating and passivating electronic circuits according to one of claims 4 and 1-3, characterized in that the basic component used in the electronic circuit or circuits is a transistor or a diode.

8. Device for encapsulating and passivating electronic circuits according to one of claims 4 and 1-3, characterized in that the electronic circuit is made of amorphous or polycrystalline silicon or cadmium selenide.

2. A device for encapsulating and passivating electronic circuits, comprising:

a substrate plate;

an electronic circuit mounted on said substrate plate for controlling electro-optical cells;

an active matrix controlling electro-optical cells mounted on said substrate plate;

an opaque layer covering said electronic circuit so as to block the photoconductivity of the active matrix, to function as a spacer and a "black matrix";

wherein said opaque layer is used to encapsulate and passivate the electronic circuit.

4. Device for encapsulating and passivating electronic circuits according to claim 2, characterized in that the encapsulating and passivating layer is deposited on the circuits and covers them completely.

3. Device for encapsulating and passivating electronic circuits, comprising:

a substrate plate;

an electronic circuit mounted on said substrate plate for controlling electro-optical cells;

an active matrix mounted on said substrate plate;

an opaque layer covering said electronic circuit to block the photoconductivity of the active matrix, to function as a spacer and a "black matrix"; and

a sealing bead deposited around the electronic circuit so as to form a sealed enclosure separate from the active matrix.