Integrated electro-optic package

• US 5,650,640 A
• Filed: 04/05/1995
• Issued: 07/22/1997
• Est. Priority Date: 04/05/1995
• Status: Expired due to Term

• Current Assignee: Motorola Solutions, Inc.
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: So, Franky, Stafford, John W., Harvey, Thomas B. III
• Primary Examiner(s): Whitehead, Carl W.
• Assistant Examiner(s): CLARK, JASMINE JHIHAN B
• Application Number:
  US08/417,360
• Time in Patent Office: 839 Days
• Field of Search: 257/81, 257/79, 257/80, 257/82, 257/83, 257/84, 257/113, 257/114, 257/184, 257/680, 257/684, 257/734, 257/749, 257/787, 257/443, 257/88
• US Class Current: 257/81
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48464 the other connecting portion not on the bonding area also being a ball bond, i.e. ball-to-ball
• 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 2924/00014 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 2924/12044 OLED
• CPC Class Codes: H01L 2924/15311 being a ball array, e.g. BGA
• CPC Class Codes: H10K 50/11 characterised by the electroluminescent [EL] layers
• CPC Class Codes: H10K 50/841 Self-supporting sealing arrangements
• CPC Class Codes: H10K 50/8423 Metallic sealing arrangements
• CPC Class Codes: H10K 50/844 Encapsulations
• CPC Class Codes: H10K 59/179 Interconnections, e.g. wiring lines or terminals

Abstract

An integrated electro-optical package including an electronic circuit mounted on a substrate, first and second groups of leads extending from the circuit through a sealing area and each lead having an end exposed in a first area, transparent conductive strips positioned in the first area and each strip contacting the exposed end of a lead in the first group, an electroluminescent medium positioned on each of the strips and defining LEDs, metallic strips positioned over the electroluminescent medium as a second electrode for each of the LEDs, each metallic strip being in contact with an exposed end of an electrical lead in the second group of leads, and a hermetic seal positioned in sealing contact with the sealing area and hermetically sealing the first area.

Claims

1. An integrated electro-optical package comprising:

an optically transparent substrate with a substantially planar surface, the substrate having a first area defined on the surface thereof, a sealing area defined on the surface thereof and surrounding the first area and an integrated circuit mounting area defined on the surface thereof adjacent the sealing area and outside of the first area;

an electronic circuit, including at least one semiconductor chip, mounted in the mounting area;

first and second groups of electrical leads electrically connected to the electronic circuit, the leads of the first and second groups extending from the mounting area through the sealing area and into the first area and each lead of each of the first and second groups having an end exposed in the first area;

a plurality of parallel, laterally spaced apart, optically transparent, electrically conductive strips positioned on a surface of the optically transparent substrate in the first area so as to define a plurality of first electrodes, each conductive strip of the plurality of conductive strips being in electrical contact with an exposed end of an electrical lead in the first group of the electrical leads so that each conductive strip of the plurality of conductive strips is in electrical contact with a different lead of the first group of leads;

an electroluminescent medium positioned on each of the plurality of first electrodes so as to define a light emitting diode in conjunction with an associated first electrode of each of the plurality of electrodes;

a layer of metal positioned over the electroluminescent medium so as to define a plurality of parallel, laterally spaced apart, metallic strips orthogonal to the plurality of conductive strips, the laterally spaced apart, metallic strips defining a second electrode for each of the light emitting diodes, each metallic strip of the plurality of metallic strips being in electrical contact with an exposed end of an electrical lead in the second group of leads so that each metallic strip of the plurality of metallic strips is in electrical contact with a different lead of the second group of leads; and

a hermetic seal positioned over the first area and in sealing contact with at least the sealing area of the surface of the optically transparent substrate so as to hermetically seal the first area.

2. An integrated electro-optical package as claimed in claim 1 wherein the optically transparent substrate is formed of optically transparent glass.

3. An integrated electro-optical package as claimed in claim 1 wherein the plurality of parallel, laterally spaced apart, optically transparent, electrically conductive strips on the surface of the substrate include a patterned layer of indium-tin oxide.

4. An integrated electro-optical package as claimed in claim 1 wherein the hermetic seal includes a hermetic sealing ring positioned in the sealing area and surrounding the first area.

5. An integrated electro-optical package as claimed in claim 1 wherein the first and second groups of electrical leads each include thin film conductors.

6. An integrated electro-optical package as claimed in claim 1 wherein the electroluminescent medium includes one of a layer of polymer and a layer of low molecular weight organic compound.

7. An integrated electro-optical package as claimed in claim 1 wherein the electronic circuit mounted in the mounting area includes a driver circuit connected to each of the first and second groups of electrical leads.

8. An integrated electro-optical package as claimed in claim 1 wherein the electroluminescent medium includes a layer of dielectric medium positioned on an upper surface of the plurality of conductive strips and the supporting substrate and defining a plurality of cavities through the layer of dielectric medium, one each of the plurality of cavities being positioned in overlying relationship to an associated first electrode of the plurality of first electrodes.

9. An integrated electro-optical package as claimed in claim 3 wherein the electrically conductive strips include a thin, optically transparent layer of metal on the patterned layer of indium-tin oxide.

10. An integrated electro-optical package as claimed in claim 9 wherein the electrically conductive strips include a second layer of indium-tin oxide positioned on the optically transparent layer of metal.

11. An integrated electro-optical package as claimed in claim 4 wherein the hermetic seal includes a metal cover engaged with the sealing ring.

12. An integrated electro-optical package as claimed in claim 4 wherein the hermetic seal includes a glass plate engaged with the sealing ring.

13. An integrated electro-optical package as claimed in claim 9 wherein the exposed ends of the first group of thin film conductors in the first area each include a gold metallized surface.

14. An integrated electro-optical package as claimed in claim 8 wherein the electroluminescent medium further includes a layer of active emitter material and a layer of a low work function metal positioned in each of the plurality of cavities on the associated first electrode.

15. An integrated electro-optical package as claimed in claim 14 wherein the layer of metal positioned over the electroluminescent medium includes a layer of ambient stable metal sealingly positioned over the cavities and in contact with the low work function metal.

16. An integrated electro-optical package comprising:

an optically transparent substrate with a substantially planar surface, the substrate having a first area defined on the surface thereof, a sealing area defined on the surface thereof and surrounding the first area and an integrated circuit mounting area defined on the surface thereof adjacent the sealing area and outside of the first area;

an electronic circuit, including at least one semiconductor chip, mounted in the mounting area;

first and second groups of electrical leads electrically connected to the electronic circuit, the leads of the first and second groups extending from the electronic circuit through the sealing area and into the first area and each lead of each of the first and second groups having an end exposed in the first area;

dielectric material positioned in the sealing area and surrounding the first area, the first and second groups of electrical leads extending through and insulated by the dielectric material;

a plurality of parallel, laterally spaced apart, optically transparent, electrically conductive strips positioned on a surface of the optically transparent substrate in the first area so as to define a plurality of first electrodes, each conductive strip of the plurality of conductive strips having an end in electrical contact with an exposed end of an electrical lead in the first group of the electrical leads so that each conductive strip of the plurality of conductive strips is in electrical contact with a different lead of the first group of leads;

an electroluminescent medium positioned on each of the plurality of first electrodes so as to define a light emitting diode in conjunction with an associated first electrode of each of the plurality of electrodes;

a layer of metal positioned over the electroluminescent medium so as to define a plurality of parallel, laterally spaced apart, metallic strips orthogonal to the plurality of conductive strips, the laterally spaced apart, metallic strips defining a second electrode for each of the light emitting diodes, each metallic strip of the plurality of metallic strips having an end in electrical contact with an exposed end of an electrical lead in the second group of leads so that each metallic strip of the plurality of metallic strips is in electrical contact with a different lead of the second group of leads;

a hermetic sealing ring positioned on a surface of the dielectric material in the sealing area and surrounding the first area; and

a hermetic cover positioned over the first area and in sealing contact with the sealing ring so as to hermetically seal the first area.

17. An integrated electro-optical package as claimed in claim 16 wherein the hermetic cover includes a metal cover engaged with the sealing ring.

18. An integrated electro-optical package as claimed in claim 16 wherein the hermetic cover includes a glass plate engaged with the sealing ring.

19. An integrated electro-optical package as claimed in claim 16 wherein the hermetic sealing ring includes a patterned layer of metal.

20. An integrated electro-optical package comprising:

a substrate with a substantially planar surface, the substrate having a first area defined on the surface thereof;

a plurality of optically transparent, electrically conductive strips positioned on the surface of the substrate in the first area so as to define a plurality of first electrodes, each conductive strip of the plurality of conductive strips including a patterned first layer of indium-tin oxide positioned on the surface of the substrate and a thin, optically transparent layer of metal positioned on the patterned first layer of indium-tin oxide;

an electroluminescent medium positioned on each of the plurality of first electrodes so as to define a light emitting diode in conjunction with an associated first electrode of each of the plurality of electrodes; and

a layer of metal positioned over the electroluminescent medium and defining a plurality of metallic strips defining a second electrode for each of the light emitting diodes.

21. An integrated electro-optical package as claimed in claim 20 wherein the electrically conductive strips include a second layer of indium-tin oxide positioned on the thin optically transparent layer of metal.