Study of Bimetallic Corrosion for Cu Interconnect and IC Packaging Using Micro-Pattern Corrosion Screening

  • Authors:
    Nick Ross (Univ. of North Texas), Oliver Chyan (Univ. of North Texas), Arindom Goswami (Univ. of North Texas), Seare Berhe (Univ. of North Texas), Po-Fu Lin (Univ. of North Texas)
    Publication ID:
    P085384
    Publication Type:
    Presentation
    Received Date:
    3-Sep-2015
    Last Edit Date:
    21-Sep-2015
    Research:
    2535.001 (University of North Texas)

Abstract

A new corrosion screening metrology utilizing micro-corrosion test patterns provides rapid in-situ corrosion evaluations relevant to Cu interconnect structure and IC packaging. In CMP related chemical environments, the Cu corrosion was found to be accelerated through an oxygen reduction reaction catalyzed by Ru contact – a potential new liner for Cu ECD. The corrosion screening discovered pyrazole is a more effective Cu corrosion inhibitor than commonly used benzotriazole (BTA) in highly alkaline TMAH solution. Relevant to Cu wire bonded assembly, microscopy time lapse imaging, SEM, EDX, and Tafel plot were employed to study Al/Cu bimetallic corrosion in acidic chloride solutions. Micropattern corrosion screening helps to identify the root cause of Al pad corrosion that leads to Cu ball lift-off in Cu wire bonded device, a fatal defect. Complete corrosion inhibition can be achieved by strategically disabling the mutually coupled cathodic and anodic reaction cycles.

Past Events

  Event Summary
20–22 September 2015
SRC
SRC
TECHCON 2015
Sunday, Sept. 20, 2015, 8 a.m. — Tuesday, Sept. 22, 2015, 10 p.m. CT
Austin, TX, United States
Technical conference and networking event for SRC members and students.

4819 Emperor Blvd, Suite 300 Durham, NC 27703 Voice: (919) 941-9400 Fax: (919) 941-9450