Influence of N2/H2 plasma treatment on chemical vapor deposited TiN multilayer structures for advanced CMOS technologies

Plasma over-treatment effect on the MOCVD-TiN contact glue layer

“…In addition to the R s reduction, the thickness of the TiN films was also decreased by the plasma treatment. Prior studies have reported that the C and H impurities of TiC x N y H z films were removed as aminocompounds (NH a (CH 3 ) b ) and hydrocarbons (C n H m ) during H 2 /N 2 plasma treatment [7][8][9][10][11] The impurity removal from the MOCVDTiN films induced the thickness reduction [5]. Fig.…”

“…For sub-130 nm silicon integrated circuits, the step coverage and the film quality of glue layers is critical for the optimization of contact resistance (R c ). In general, the Ti and TiN films are deposited by ionized-metal-plasma (IMP) and metallorganic CVD (MOCVD), respectively, to improve the step coverage in high-aspect-ratio features [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17]. In the MOCVD-TiN deposition, tetrakisdimethylaminotitanium (TDMAT) is typically used as a precursor to obtain chloride-free TiN films [1,2].…”

“…In order to improve the electrical properties of MOCVD-TiN films, an in-situ plasma treatment using a hydrogen (H 2 )/nitrogen (N 2 ) gas mixture is commonly employed to lower the level of C impurities and to form a crystallized TiN film [4][5][6][7][8][9]. The H 2 plasma is considered to have chemical reactivity that reduces C impurities while the N 2 plasma is believed to have a physical dominant reaction between activated nitrogen species and MOCVDTiN films [7][8][9][10][11].…”

“…Since the electrical properties of MOCVD-TiN films are highly plasma-treatment sensitive, many researching have tried to understand the role of plasma post-treatment in MOCVD-TiN deposition [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17]. However, most prior researcher has focused on the composition, resistivity change, and barrier property of blanket films but not on the electrical properties of patterned wafers.…”

Reversible Tuning of the Surface Chemical Reactivity of Titanium Nitride and Nitride−Carbide Diffusion Barrier Thin Films

“…Since carbon increases the resistivity of barrier films, , several strategies were developed to reduce the +carbon content in nitride films, including the use of easily controllable film deposition techniques (such as atomic layer deposition, ALD) ,,− ,− and the implementation of postdeposition (e.g., plasma ,− and thermal − ) treatments. However, interest in nitride−carbide films has been boosted recently because the crystallinity of pure nitrides is disrupted by the presence of carbon, avoiding potential diffusion through grain boundaries. ,, Tungsten nitride−carbide (WNC) is currently receiving considerable attention as a copper diffusion barrier, − and nitride−carbides of titanium (TiNC) and tantalum (TaNC) have been investigated for this purpose as well. ,− Oxygen incorporation, which also increases the resistivity of these films and occurs readily upon exposure to ambient atmospheric conditions following vacuum deposition, is a more persistent problem that has also received substantial attention. ,,,,,− …”