Effect of copper barrier dielectric deposition process on characterization of copper interconnect

Abstract

The effect of copper (Cu) barrier film deposition process on the Cu interconnects was investigated, including the waiting time between Cu chemical mechanical polishing and the barrier dielectric deposition, the preheating time, ammonia (NH(3)) plasma treatment prior to the barrier dielectric deposition, and various types of barrier dielectric. Effective treatment on the Cu surface ensures superior conductivity of the Cu interconnects and enhances the adhesion between Cu and the barrier film, causing a longer electromigration failure time. However, excessive thermal time (preheating, treatment, and deposition time) induces the Cu hillock defect. Furthermore, silicon nitride (SiN) film with a lower hydrogen content has better physical and reliability performances. Therefore, optimization of the Cu barrier deposition process is important to improve the performance of Cu interconnects. (C) 2010 American Vacuum Society. [DOI: 10.1116/1.3425631

Stability and migration of small copper clusters in amorphous dielectrics

“…The dissolution and clustering of metallic ions in dielectric materials is important for a wide range of applications including microelectronics where metallic interconnects can dissolve into its surrounding dielectric [1][2][3][4], photonics where metallic nanoclusters are used to engineer optical properties [1,5], and electrochemical metallization (ECM) cells for resistive switching random access memory (RRAM). RRAM devices operate by switching between low and high resistance states and ECM cells are promising candidates for next-generation non-volatile memory due to the potential of high scalability, fast switching speeds and ultra low power operation [6][7][8][9][10].…”

Comparison of H2and NH3Treatments for Copper Interconnects

“…However, in a real Cu and low-k dielectric dual damascene process, Cu can be oxidized by exposure to air before the diffusion barrier is deposited. Thus the formed Cu oxide layer negatively affects the electrical performance and reliability of devices [8,9]. Therefore, a chemical reaction to remove this native Cu oxide is required before the barrier layer is deposited to improve the adhesion between the Cu film and the barrier layer.…”

Ab initiostudy of Cu diffusion inα-cristobalite

“…However, Cu still interacts with SiO 2 , which can lead to diffusion of Cu ions through the dielectric layer and to metallization of SiO 2 . One result of this interaction is the degradation of the dielectric properties [3,4].…”

“…The mean-square displacement r(t) 2 of the Cu ion as a function of time (b) calculated as an average from 15 MD simulations. The black dashed lines corresponds to the fitting function from equation(4). Also the mean-square displacements of motion in the x, y and z directions are shown.…”