Control of deposition profile of Cu for large-scale integration (LSI) interconnects by plasma chemical vapor deposition

Abstract

H-assisted plasma chemical vapor deposition (HAPCVD) realizes control of deposition profile of Cu in trenches. The key to the control is ion irradiation to surfaces. With increasing the flux and energy of ions, the profile changes from conformal to subconformal and then to an anisotropic one, for which Cu material is filled from the bottom of the trench without deposition on the sidewall. H3+ and ArH+ are identified as the major ionic species which contribute to the control, and hence the deposition profile also depends on a ratio R = H2/(Ar + H2).

Effects of discharge voltage on the characteristics of a-C:H films prepared by H-assisted Plasma CVD method

“…1 [16][17][18][19][20][21]. The main discharge, which was sustained between a mesh powered electrode of 85 mm in diameter and a plane substrate electrode of 85 mm in diameter at a distance of 32 mm, was employed to produce carbon containing radicals as precursors.…”

Emission spectroscopy of Ar + H2+ C7H8plasmas: C7H8flow rate dependence and pressure dependence

“…Experiments were performed using the H-assisted plasma CVD reactor, in which a capacitivelycoupled main discharge and an inductively-coupled discharge of H atom source were sustained as shown in figure 1 [5][6][7][8][9][10][11][12][13][14][15][16]. The main discharge, which was sustained between a mesh powered electrode of 85 mm in diameter and a plane substrate electrode of 85 mm in diameter at a distance of 33 mm, was employed to produce carbon containing radicals as precursors.…”

“…So far, we have succeeded in controlling deposition profiles of copper films on trench substrates, and realized sub-conformal, conformal and anisotropic deposition profiles [5][6][7][8][9][10]. Then the methods of controlling deposition profiles have been applied to carbon films, and realized sub-conformal, conformal and anisotropic deposition profiles, for which carbon is deposited only to the top or without sidewall deposition [11][12][13][14][15][16].…”

Discharge power dependence of Hα intensity and electron density of Ar+H2 discharges in H-assisted plasma CVD reactor

“…To solve the problems associated with sub-conformal and conformal deposition, we have realized anisotropic deposition of Cu, for which Cu is filled preferentially from the bottom of trenches without being deposited on the sidewall of trenches [7,8]. Fig.…”

“…Moreover, irradiation of H atoms on the surfaces removes impurities in films. Therefore, a high ion flux as well as a high H flux on surfaces are needed to increase the deposition rate [8]. To find such deposition condition, we have carried out measurements of emission intensities and electron density in H-assisted plasma CVD reactor, since emission intensities give information about radical generation rates and electron density is one of the key parameters of CVD plasmas.…”