IC chip coating material and vacuum fluorescent display device using same

• US 8,053,896 B2
• Filed: 02/14/2006
• Issued: 11/08/2011
• Est. Priority Date: 02/14/2005
• Status: Active Grant

• Current Assignee: Futaba Corporation
• Original Assignee: Fatuba Corporation
• Inventors: Kato, Masahiro, Fujiwara, Kouji, Yasuoka, Yusuke, Watanabe, Teruo
• Primary Examiner(s): Hoang; Quoc
• Assistant Examiner(s): Tran; Tony
• Application Number:
  US11/353,070
• Publication Number:
  US 20060180825A1
• Time in Patent Office: 2,093 Days
• Field of Search: 257/765, 257/E31.129
• US Class Current: 257/765
• CPC Class Codes: H01J 29/96 One or more circuit elements structurally associated with the tube
• CPC Class Codes: H01L 2224/32225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/45015 being circular
• CPC Class Codes: H01L 2224/45099 Material
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48227 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/73204 the bump connector being embedded into the layer connector
• CPC Class Codes: H01L 2224/73265 Layer and wire connectors
• CPC Class Codes: H01L 2224/83192 wherein the layer connectors are disposed only on another item or body to be connected to the semiconductor or solid-state body
• CPC Class Codes: H01L 2224/83801 Soldering or alloying
• CPC Class Codes: H01L 2224/8592 Applying permanent coating, e.g. protective coating
• CPC Class Codes: H01L 23/291 Oxides or nitrides or carbides, e.g. ceramics, glass
• CPC Class Codes: H01L 24/48 of an individual wire connector
• CPC Class Codes: H01L 24/73 Means for bonding being of different types provided for in two or more of groups H01L24/10, H01L24/18, H01L24/26, H01L24/34, H01L24/42, H01L24/50, H01L24/63, H01L24/71
• CPC Class Codes: H01L 24/83 using a layer connector
• 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 2924/00012 Relevant to the scope of the group, the symbol of which is combined with the symbol of this group
• 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 2924/01025 Manganese [Mn]
• CPC Class Codes: H01L 2924/01079 Gold [Au]
• CPC Class Codes: H01L 2924/01087 : Francium [Fr]
• CPC Class Codes: H01L 2924/10253 : Silicon [Si]
• CPC Class Codes: H01L 2924/12044 : OLED
• CPC Class Codes: H01L 2924/14 : Integrated circuits
• CPC Class Codes: H01L 2924/181 : Encapsulation
• CPC Class Codes: H01L 2924/1815 : Shape
• CPC Class Codes: H01L 2924/207 : Diameter ranges
• CPC Class Codes: H01L 2924/3512 : Cracking

Abstract

An IC chip coating material includes first metal oxide particles; a metal alkoxide; an organic solvent; and second metal oxide particles and/or flat particles of a composite oxide, the second metal oxide particles having a composition identical to or different from that of the first metal oxide particles and also having a mean particle size and/or a shape different from that of the first metal oxide particles. Further, a vacuum fluorescent display device includes an IC chip, wherein the IC chip is at least partially coated by a coating material layer including the first metal oxide particles; a metal forming metal alkoxide; and the second metal oxide particles and/or flat particles of a composite oxide.

Claims

1. A vacuum fluorescent display device comprising:

i) an IC chip,

ii) one or more bonding wires, wherein each of the bonding wires is connected to an electrode of the IC chip, and

wherein the IC chip and the bonding wires are entirely coated by a coating material layer including first metal oxide particles;

second metal oxide particles ; and

third metal oxide particles formed from a metal alkoxide,

wherein the first and the second metal oxide particles include oxide particles of at least one metal selected from the group consisting of Fe, Cr and Mn and a composition of the first metal oxide particles is different from that of the second metal oxide particles,

wherein the coating material layer further includes flat particles of a composite oxide, and

wherein the composite oxide is mica.

2. The vacuum fluorescent display device of claim 1, wherein the coating material layer for coating the IC chip is black.

3. The vacuum fluorescent display device of claim 1, wherein a shape of the first metal oxide particles is different from that of the second metal oxide particles.

4. The vacuum fluorescent display device of claim 1, wherein a thickness of the coating material layer ranges from 50 to 250 μ

m.

5. The vacuum fluorescent display device of claim 1, wherein a mean particle size ratio of the first metal oxide particles to the second metal oxide particles is set to be equal to or greater than 5.

6. The vacuum fluorescent display device of claim 1, wherein the coating material layer serves as a layer protecting the IC chip from the surroundings thereof.

7. The vacuum fluorescent display device of claim 1, wherein the first metal oxide particles and second metal oxide particles comprise Fe, Mn, and Cr.

8. The vacuum fluorescent display device of claim 1, wherein the third metal oxide particles include alumina as a fixing material which fixes the coating material layer.

9. The vacuum fluorescent display device of claim 1, wherein a size of the metal oxide particles of Fe, Cr or Mn is 3.5 μ

m and a size of the flat particles is 25 μ

m.

10. The vacuum fluorescent display device of claim 9, wherein a ratio in weight of the first and the second metal oxide particles to the flat particles is 4 to 1, and a total amount of the first and the second metal oxide and the flat particles ranges from 97 to 99 wt % of the coating material layer.

11. A vacuum fluorescent display device comprising:

i) an IC chip, and

ii) one or more bonding wires,

wherein each of the bonding wires are connected to an electrode of the IC chip,

wherein the IC chip and the bonding wires are entirely coated by a coating material layer including first metal oxide particles;

second metal oxide particles; and

third metal oxide particles from a metal alkoxide,

wherein the first metal oxide particles include oxide particles of at least one metal selected from the group consisting of Fe, Cr, Mn, Al and Si,

wherein the second metal oxide particles include metal oxide particles of at least one metal oxide selected from the group consisting of Al oxide and Si oxide,

wherein the coating material layer further includes flat particles of a composite oxide,

wherein the composite oxide is mica, and

wherein the first metal oxide particles and second metal oxide particles comprise Fe, Mn, and Cr.