Method for improving bondability for deep-submicron integrated circuit package

• US 6,110,816 A
• Filed: 03/05/1999
• Issued: 08/29/2000
• Est. Priority Date: 03/05/1999
• Status: Expired due to Term

• Current Assignee: Taiwan Semiconductor Manufacturing Company Limited
• Original Assignee: Taiwan Semiconductor Manufacturing Company Limited
• Inventors: Huang, Yung-Sheng, Hsieh, Hung-Chang, Hsieh, Han-Chang
• Primary Examiner(s): Chaudhuri, Olik
• Assistant Examiner(s): Chambliss, Alonzo
• Application Number:
  US09/261,999
• Time in Patent Office: 543 Days
• Field of Search: 438/612, 438/613, 438/614, 438/617, 438/622, 438/637, 438/666, 438/611, 438/638, 438/639, 438/640, 438/672
• US Class Current: 438/612
• CPC Class Codes: H01L 2224/02166 Collar structures
• CPC Class Codes: H01L 2224/04042 Bonding areas specifically adapted for wire connectors, e.g. wirebond pads
• CPC Class Codes: H01L 2224/05073 Single internal layer
• CPC Class Codes: H01L 2224/05093 of a plurality of vias
• CPC Class Codes: H01L 2224/05187 Ceramics, e.g. crystalline carbides, nitrides or oxides glass ceramics H01L2224/05188
• CPC Class Codes: H01L 2224/05556 in side view
• CPC Class Codes: H01L 2224/05557 comprising protrusions or indentations
• CPC Class Codes: H01L 2224/05624 Aluminium [Al] as principal constituent
• CPC Class Codes: H01L 2224/05647 Copper [Cu] as principal constituent
• CPC Class Codes: H01L 2224/45099 Material
• CPC Class Codes: H01L 2224/4807 of bonding interfaces, e.g. interlocking features
• CPC Class Codes: H01L 2224/48453 of the interface with the bonding area
• CPC Class Codes: H01L 2224/48463 the connecting portion on the bonding area of the semiconductor or solid-state body being a ball bond
• CPC Class Codes: H01L 2224/78 Apparatus for connecting with wire connectors
• CPC Class Codes: H01L 2224/78301 Capillary
• CPC Class Codes: H01L 2224/85045 using a corona discharge, e.g. electronic flame off [EFO]
• CPC Class Codes: H01L 2224/85201 Compression bonding
• CPC Class Codes: H01L 2224/85203 Thermocompression bonding
• CPC Class Codes: H01L 2224/85205 Ultrasonic bonding
• CPC Class Codes: H01L 2224/85399 Material
• CPC Class Codes: H01L 24/03 : Manufacturing methods
• CPC Class Codes: H01L 24/05 : of an individual bonding area
• CPC Class Codes: H01L 24/48 : of an individual wire connector
• CPC Class Codes: H01L 24/85 : using a wire connector wire bonding in general B23K20/004
• 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 2924/01013 : Aluminum [Al]
• CPC Class Codes: H01L 2924/01014 : Silicon [Si]
• CPC Class Codes: H01L 2924/01022 : Titanium [Ti]
• CPC Class Codes: H01L 2924/01029 : Copper [Cu]
• CPC Class Codes: H01L 2924/01039 : Yttrium [Y]
• CPC Class Codes: H01L 2924/01074 : Tungsten [W]
• CPC Class Codes: H01L 2924/01327 : Intermediate phases, i.e. intermetallics compounds
• CPC Class Codes: H01L 2924/04941 : TiN
• CPC Class Codes: H01L 2924/04953 : TaN
• CPC Class Codes: H01L 2924/10253 : Silicon [Si]
• CPC Class Codes: H01L 2924/14 : Integrated circuits

Abstract

A method is adapted to form wire interconnect pads on integrated circuit devices and includes the steps of providing a semiconductor substrate having an aluminum-copper top metal layer, and a titanium nitride layer covering the aluminum-copper top metal layer, and a photoresist coating applied to the titanium nitride layer. The photoresist coating is partially exposed and partially developed to form openings for etching an array of submicron size holes. Etching through the titanium nitride layer to the aluminum-copper layer, by way of the partially developed photoresist, forms a rough textured surface profile in the array of cavities, with diameters of less than 0.3 um, etched in the aluminum copper layer. After stripping of the photoresist and depositing a passivation film, windows are formed delineating improved bond pads for wire bonding. The textured cavities increase the surface area of the bond pads and provide improved bondability for the 0.35 and 0.3 um IC devices.

Claims

1. A method for forming a wire ball bonding surface site on a semiconductor die comprising the steps of:

providing a semiconductor substrate having a top electically conducting layer, and

an overlying layer covering said top electrically conducting layer, and

a photoresist applied to said overlying layer;

patterning said photoresist to form an array of submicron size holes;

etching openings through said overlying layer to said top electrically conducting layer, and forming a rough textured surface profile in said top electrically conducting layer through said openings of said overlying layer;

depositing a passivation film over said overlying layer and forming wiring pad windows for wire ball bonding.

2. The method of claim 1 wherein said overlying layer is titanium nitride.

3. The method of claim 1 wherein said top electrically conducting layer is aluminum-copper.

4. The method of claim 1 wherein patterning said photoresist coating is accomplished using a photomask having a plurality of hole arrays with submicron hole diameters.

5. The method of claim 1 wherein patterning of said photoresist to form a plurality of hole arrays, said patterning is done by partially exposing and partially developing of said photoresist.

6. The method of claim 5 wherein etching of said submicron size holes through said partially exposed and partially developed photoresist produces etched hole diameters of less than 0.3 um.

7. The method of claim 5 wherein etching of said submicron size holes through said partially exposed and partially developed photoresist produces a plurality of rough textured semi-ellipsoidal recess arrays in the aluminum copper layer.

8. The method of claim 7 wherein said rough textured semi-ellipsoidal array of recesses increases surface area for wire ball bonding.

9. The method of claim 7 wherein said rough textured semi-ellipsoidal array of recesses provides a mechanical interlock bond between a wire ball and bond pad.