Frank M. Cerio

Film properties of Ti/TiN bilayers deposited sequentially by ionized physical vapor deposition

Ionized physical vapor deposition (iPVD) has received much attention as a method for depositing material at the bottom and on the sidewalls of the high aspect ratio features proposed for sub-0.25 micron integrated circuits. In this article, we describe the film properties of Ti/TiN bilayers deposited sequentially using the iPVD technique. The experimental configuration consisted of a planar magnetron sputtering source in combination with an inductively coupled RF plasma. TiN was reactively sputtered from a titanium target which remained non-nitrided throughout the deposition, a process commonly referred to in non-ionized PVD as operating in the non-nitrided mode (NNM). These films were analyzed by cross-sectional scanning electron microscopy and transmission electron microscopy, automated four-point sheet resistance probe, x-ray diffraction, x-ray fluorescence, stress gauge, and Rutherford backscattering. Highly oriented 〈111〉 TiN was observed on 〈002〉 oriented Ti underlayers. At via aspect ratios of 4:1 ...

Low resistance wiring and 2Xnm void free fill with CVD Ruthenium liner and DirectSeed TM copper

Chemical vapor deposited (CVD) Ruthenium liners and DirectSeedTM (DS) copper were used with advanced Electrofill processes to provide lower resistance wiring compared to results using CVD Ru and conventional physical vapor deposited (PVD) Cu seed for back end of line (BEOL) structures. Different annealing temperatures and simulated BEOL thermal stress builds were used to show the difference in resistance. The grain size was also compared to show that the Ru/DS process had larger grains than the Ru/flash-Cu (F-Cu) seed. To further show the advantage of the Ru/DS seed process as a solution for future generations, 2X nm trenches were shown to have complete gap fill and thereby eliminating the need for conventional PVD Cu seed.