Tza-Jing Gung

Control of bombardment energy and energetic species toward a superdense titanium nitride film

TiN deposited by dc magnetron sputtering has been widely used as a hard mask material for dielectric patterning in multilevel Cu interconnects. Typically inside a “poison-mode” regime, the film density is 4.5–4.9 g/cm3. The microstructure, varying from columnar structure to nanocrystalline, is controlled by both thermodynamics and surface kinetics through ionization, substrate bias, target voltage, etc. A relatively low density film can be correlated with a porous columnar structure, low mechanical robustness, and weak resistance to plasma etching. However, with controlled growth, an applied substrate bias does not create resputtering and crystal defects. Instead, the authors create film with a maximum density of 5.3 g/cm3. In this high density film, carrier scatterings through grain boundary are greatly suppressed and the film resistivity is as low as 95 μΩ cm, which brings additional benefits as a conductive capping layer. As it is deposited at room temperature, the process minimizes the thermal budget ...

Modeling and Simulation of Physical Vapor Deposition/Etching Plasmas

A new physical vapor deposition source is developed to meet the challenges of barrier deposition for sub 100nm devices. The source employs multi-step process to deposit thin, conformal and uniform barrier films. This paper describes reactor scale modeling and simulation of deposition and etching plasmas used for barrier deposition. The modeling and simulation in tandem with experimental data demonstrate that the chamber can be used to independently control the particle fluxes as per the requirements of the deposition and etching steps. The simulation results were qualitatively used to optimize the ion flux uniformity by altering the magnetic fields near the wafer.© 2005 ASME