Investigation on Electrical Properties of RF Sputtered Deposited BCN Thin Films

Abstract

The ever increasing advancements in semiconductor technology and continuous scaling of CMOS devices mandate the need for new dielectric materials with low-k values. The interconnect delay can be reduced not only by the resistance of the conductor but also by decreasing the capacitance of dielectric layer. Also cross-talk is a major issue faced by semiconductor industry due to high value of k of the inter-dielectric layer (IDL) in a multilevel wiring scheme in Si ultra large scale integrated circuit (ULSI) devices. In order to reduce the time delay, it is necessary to introduce a wiring metal with low resistivity and a high quality insulating film with a low dielectric constant which leads to a reduction of the wiring capacitance. Boron carbon nitride (BCN) films are prepared by reactive magnetron sputtering from a B4C target and deposited to make metal-insulator-metal (MIM) sandwich structures using aluminum as the top and bottom electrodes. BCN films are deposited at various N2/Ar gas flow ratios, substrate temperatures and process pressures. The electrical characterization of the MIM devices includes capacitance vs. voltage (C-V), current vs voltage, and breakdown voltage characteristics. The above characterizations are performed as a function of deposition parameters. iv To my grandfather late Mr. H Hanumanthaiah and my parents v ACKNOWLEDGMENTS I would like to thank my advisor, Dr. Kalpathy B Sundaram, for his continuous commitment to help and support me through my graduate career. His advice, technical and otherwise, has been valuable to my experience as a graduate student and a s a person. I would also like to thank my committee members, Dr. Jiann S Yuan and Dr. Mingjie Lin, for their support throughout my years at UCF. My heartfelt gratitude goes out to all of my colleagues at the lab-Giji Skaria, Ritika Oswal. Giji was very much instrumental in helping me to perform Vacuum Evaporation experiments and some basic electrical debugging. I would like to thank my father Mr. H Prakash and my mother Mrs. Asha Prakash for their constant motivation and for instilling confidence in me at every step. Also I would like to thank my sister Ms. Ananya Prakash for her love and support. And last but not the least I would like to thank my grandparents and all my relatives and friends who stood by my side during ups and downs of my academic life here.

A brief overview of RF sputtering deposition of boron carbon nitride (BCN) thin films

“…Furthermore, with increasing the substrate temperature, the breakdown voltage was increased initially then followed by a slight decrease. The resistivity of the deposited BCN films was noticed to be constant and can be slightly changed by increasing the substrate temperature [114].…”