Abstract
A liquid mixture formed from two benign chemicals, urea and choline chloride, in the molar ratio of 2:1 has been evaluated for post etch residue (PER) removal from copper surface. Residue films were prepared by etching DUV photoresist films coated on copper in CF4/O2 plasma. Film removal was evaluated under immersion cleaning conditions using X-ray photoelectron spectroscopy and scanning electron microscopy and verified using electrochemical impedance spectroscopy measurements. The residue film was effectively removed in the temperature range of 40-70C. The results of this study show that choline chloride and urea based DES system has the potential to function as a back end of line cleaning formulation.
Original language | English (US) |
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Pages (from-to) | H358-H361 |
Journal | Electrochemical and Solid-State Letters |
Volume | 14 |
Issue number | 9 |
DOIs | |
State | Published - 2011 |
Externally published | Yes |
ASJC Scopus subject areas
- General Chemical Engineering
- General Materials Science
- Physical and Theoretical Chemistry
- Electrochemistry
- Electrical and Electronic Engineering