Anodized aluminum substrate having increased breakdown voltage

• US 5,534,356 A
• Filed: 04/26/1995
• Issued: 07/09/1996
• Est. Priority Date: 04/26/1995
• Status: Expired due to Fees

• Current Assignee: Advanced Technology Incubator Incorporated
• Original Assignee: OLIN Corporation
• Inventors: Parthasarathi, Arvind, Liang, Dexin, Mahulikar, Deepak, Holmes, Michael A., Sagiv, Efraim, Ramirez, German J., Jalota, Satish, Brock, Andrew J., Schlater, Jeffrey M.
• Primary Examiner(s): Ryan, Patrick J.
• Assistant Examiner(s): LAM, CATHY FONG FONG
• Application Number:
  US08/427,921
• Time in Patent Office: 440 Days
• Field of Search: 428/615, 428/209, 428/650, 205/80, 205/105
• US Class Current: 428/615
• CPC Class Codes: H01L 2224/16225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 23/142 Metallic substrates having insulating layers
• 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 2924/01327 Intermediate phases, i.e. intermetallics compounds
• CPC Class Codes: H05K 1/053 the metal substrate being covered by an inorganic insulating layer
• CPC Class Codes: H05K 1/056 the metal substrate being covered by an organic insulating layer
• CPC Class Codes: Y10T 428/12493 Composite; i.e., plural, adjacent, spatially distinct metal components [e.g., layers, joint, etc.]
• CPC Class Codes: Y10T 428/12556 Organic component
• CPC Class Codes: Y10T 428/12736 Al-base component
• CPC Class Codes: Y10T 428/24917 including metal layer

Abstract

There is provided an anodizable aluminum substrate having an increased breakdown voltage. The increase in breakdown voltage is achieved by selecting an appropriate aluminum alloy and appropriate processing parameters. Sealing the anodic film increases the breakdown voltage by decreasing corrosion. A preferred sealant is an epoxy cresol novolac having a low room temperature viscosity that cures to a highly cross-linked polymer.

Claims

1. A component for electronic applications comprising:

an anodizable metal core having a yield strength in excess of 30 ksi; and

an anodic film coating at least a portion of said core wherein the alloy constituents within said anodizable metal core are substantially soluble in an anodization electrolyte thereby increasing the breakdown voltage.

2. The component of claim 1 wherein said alloy constituents are substantially soluble in a sulfuric acid based electrolyte.

3. The component of claim 2 wherein a predominant alloy constituent is magnesium.

4. The component of claim 3 wherein said core is an aluminum alloy of the 5000 series.

5. The component of claim 4 wherein said core is selected from the group consisting of:

2.2%-2.8%, by weight, of magnesium and the balance aluminum;

0.6%-1.0% by weight, of magnesium and the balance aluminum; and

0.08%-1.2% magnesium, 0.15%-0.45% manganese and the balance aluminum.