Title :
Process and reliability of SF6/O2 plasma etched copper TSVs
Author :
Filipovic, Lado ; de Orio, R.L. ; Selberherr, Siegfried
Author_Institution :
Inst. for Microelectron., Tech. Univ. Wien, Vienna, Austria
Abstract :
The formation of a TSV for three-dimensional interconnects using SF6/O2 plasma is explored. Adjusting the O2 gas concentration to 45 sccm, while the SF6 concentration is set to 35 sccm, produced the best combination of chemical and physical etching to provide sidewall angles of 88°. Three TSV aspect ratios are etched (5/58, 10/100, and 20/100 μm) and subsequently analyzed using the finite element method. The TSVs´ series resistance, current density, thermo-mechanical stress, and electromigration induced stress after 300 hours of operation at a 2MA/cm2 current density are analyzed. An additional comparison to ideal TSVs with sidewall angles at 90° is performed.
Keywords :
current density; electromigration; etching; finite element analysis; integrated circuit interconnections; integrated circuit reliability; sputter etching; three-dimensional integrated circuits; Cu; SF6-O2; chemical etching; current density; electromigration; finite element method; gas concentration; physical etching; plasma etched copper TSV; reliability; series resistance; thermomechanical stress; three-dimensional interconnects; time 300 hour; Abstracts; Etching; Presses; Reliability; Silicon; Stress; Sulfur hexafluoride;
Conference_Titel :
Thermal, mechanical and multi-physics simulation and experiments in microelectronics and microsystems (eurosime), 2014 15th international conference on
Conference_Location :
Ghent
Print_ISBN :
978-1-4799-4791-1
DOI :
10.1109/EuroSimE.2014.6813768
