TY - GEN
T1 - Glyoxylic acid as reducing agent for electroless copper deposition on cobalt liner
AU - Inoue, Fumihiro
AU - Philipsen, Harold
AU - Van Der Veen, Marleen H.
AU - Van Huylenbroeck, Stefaan
AU - Armini, Silvia
AU - Struyf, Herbert
AU - Shingubara, Shoso
AU - Tanaka, Tetsu
N1 - Publisher Copyright:
© The Electrochemical Society.
PY - 2014
Y1 - 2014
N2 - Electroless deposition of Cu was investigated on thin Co layer for through Si via with high aspect ratio structure. The electroless deposition bath was optimized for minimizing Co corrosion during Cu nucleation by using electrochemical analysis. Glyoxylic acid, which is known as non-toxic reducing agent for electroless Cu deposition, showed anodic oxidation on Co, which did not appear for the case of formaldehyde. Furthermore, ratio of complexing agent and Cu ion also impacted Co corrosion; free complexing agent in the electroless deposition bath accelerated corrosion of Co. The optimized electroless bath which contained glyoxylic acid as reducing agent and non-free EDTA performed in 3 μm × 50 μm TSV, the electroless deposited Cu layer could serve as a seed layer for TSV filling by electrodeposition. The electroless Cu layer was continuously deposited without missing of continuity of Co layer even close to the bottom of TSV.
AB - Electroless deposition of Cu was investigated on thin Co layer for through Si via with high aspect ratio structure. The electroless deposition bath was optimized for minimizing Co corrosion during Cu nucleation by using electrochemical analysis. Glyoxylic acid, which is known as non-toxic reducing agent for electroless Cu deposition, showed anodic oxidation on Co, which did not appear for the case of formaldehyde. Furthermore, ratio of complexing agent and Cu ion also impacted Co corrosion; free complexing agent in the electroless deposition bath accelerated corrosion of Co. The optimized electroless bath which contained glyoxylic acid as reducing agent and non-free EDTA performed in 3 μm × 50 μm TSV, the electroless deposited Cu layer could serve as a seed layer for TSV filling by electrodeposition. The electroless Cu layer was continuously deposited without missing of continuity of Co layer even close to the bottom of TSV.
UR - http://www.scopus.com/inward/record.url?scp=84930268971&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84930268971&partnerID=8YFLogxK
U2 - 10.1149/06440.0063ecst
DO - 10.1149/06440.0063ecst
M3 - Conference contribution
AN - SCOPUS:84930268971
T3 - ECS Transactions
SP - 63
EP - 75
BT - Processing Materials of 3D Interconnects, Damascene, and Electronics Packaging 6
A2 - Kondo, K.
A2 - Akolkar, R.
A2 - Barkey, D. P.
A2 - Dow, W. P.
A2 - Hayase, M.
A2 - Koyanagi, M.
A2 - Mathad, S.
A2 - Ramm, P.
A2 - Roozeboom, F.
A2 - Shingubara, S.
PB - Electrochemical Society Inc.
T2 - Symposium on Processing Materials of 3D Interconnects, Damascene, and Electronics Packaging 6 - 2014 ECS and SMEQ Joint International Meeting
Y2 - 5 October 2014 through 9 October 2014
ER -