The hydrogenated diamond-like carbon (DLCH) film with 1-µm thickness is deposited by direct hydrocarbon gas ion beam method on silicon wafer and annealed at 400 • C. Detailed Raman spectra feature are fitted from nine sets of different peak fitting functions, including Gaussian, Lorentzian and Breit-Wigner-Fano (BWF) functions. These fitting results obtained from a two-peak combination show some specific variances on the G peak position, FWHM G and I D /I G ratio for as-deposited and as-annealed DLCH films. The most popular two-peak fitting method with full Gaussian function tends to exhibit a higher ratio of the G peak position shift and higher I D /I G ratio than others fitting methods, the drastic difference among the most popular G (G) & G (D) and B (G) & L (D) schemes also have brought out in I D /I G ratio. However, for a more complex four-peak Gaussian function fitting Raman spectra, the I D /I G ratio is close to that of a two-peak fitting function with a mixture functions of BWF (G) and L (D). Furthermore, a series of systematic peak fitting procedures and comparisons of Raman spectra have been discussed in this study.

The hydrogened diamond like carbon film (DLCH) with 1 mm thickness is made by hydrocarbon gas ion beam deposition method. The relationship between I D =I G ratio fitted from visible Raman spectra and sp 2 /sp 3 ratio done from XPS spectra of DLCH film shows a trend. The I D =I G ratio of deconvoluted visible Raman spectra shows a correlation with sp 2 /sp 3 ratio from XPS spectra as annealing temperature increases, the graphitization and the disorder increase. The I D =I G ratios fitted with two-curve Gaussian functions of Raman spectra tend to be proportional to sp 2 /sp 3 ratio fitted with three-curve with 100% Gaussian function of XPS spectra when post annealed treatment is below 400 C and without severe oxidation.

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This paper describes an acid-based electroless Cu deposition system employing CuCl 2-HNO 3 chemistry in a HF-NH 4 F buffer solution. With the help of nitric acid, Cu can be deposited on SiO 2 /Ta/TaN substrate without the insertion of a Cu seed layer. The deposition rate is found to decrease with increasing ͓HNO 3 ͔ in the solution. The roles of ͓NO 3 Ϫ ͔, ͓F Ϫ ͔, ͓Cl Ϫ ͔, ͓NH 4 Ϫ ͔, Si, and TaN in the system are identified based on split experiments. Si acts as the reducing agent while ͓F Ϫ ͔ and ͓Cl Ϫ ͔ ions form complexions with and transmit electrons to Cu 2ϩ. Overall, a deposition rate of 2700 Å/min with a Cu resistivity of 2.35 ⍀ cm can be achieved.

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This paper describes the kinetics involved in the acid-based electroless Cu deposition system employing CuCl 2 -HNO 3 chemistry in a HF-NH 4 F buffer solution. The rate equation is set up as a function of concentrations of active chemical components involved, and rate orders are determined to evaluate the contribution from each component. The deposition rate of Cu is found most sensitive to variation in ͓Cl Ϫ ͔ concentrations, followed by that of ͓Cu 2ϩ ͔ and ͓F Ϫ ͔. The activation energy derived from deposition at different temperatures is 0.445 eV. Grain size of deposited Cu films is influenced strongly by deposition rate. Electrical resistivity of Cu films is dominated by the amount of point defects and microvoids present right after deposition, and by grain size after a 300°C anneal.Electroless plating provides a viable alternative to electroplating for Cu thin-film deposition in the era of Cu-based multilevel interconnect for microelectronic devices. 1 Besides its capability of filling high-aspect-ratio pattern structure, electroless plating offers additional advantages such as low cost and simpler chemistry.Most existing electroless Cu plating processes adopt base solutions with copper sulfate as the Cu ion source, ethylenedinitroloacetate ͑EDTA͒ as the complexing agent, formaldehyde as reducing agents, tetramethylammonium hydroxide ͑TMAH͒ or alkali solution as pH buffer, and some surfactant and stabilizer added to improve step coverage and bath stability, respectively. This chemical formulation has been studied extensively over the past twenty years and has been applied to the manufacture of circuit boards.In the first part of this study, 2 we proposed an acid-based CuCl 2 -HNO 3 electroless Cu plating solution with HF-NH 4 F as pH buffer. An optimum deposition rate of ϳ2700 Å/min directly on TaN substrate and a resistivity of 2.35 ⍀ cm can be achieved at pH 4.70. CuCl 2 , when dissolved in the solution, provides the ͓Cu 2ϩ ͔ ions, which are catalyzed by HNO 3 on TaN surface and reduced by Si to form Cu deposits. ͓Cl Ϫ ͔ and ͓F Ϫ ͔ ions act as complexing agents and transmit the electrons from Si to ͓Cu 2ϩ ͔. Cu deposition rate exhibits a decreasing trend with increasing ͓HNO 3 ͔ concentration in the bath. Adding ͓HF͔ or ͓NH 4 F͔ into the bath, on the other hand, enhances the deposition rate to a peak level, after which it saturates and declines.As an extension of our previous study, we explore the kinetics and material issues of the system in this contribution. Concentration of the active components and temperature used in the system are varied in order to deduce the reaction rate orders and activation energy. Evolution of grain size and resistivity with ͓Cu 2ϩ ͔ concentration in the chemical bath are analyzed. The effects of postdeposition anneal on resistivity, microstructure, and preferred crystal orientation of Cu thin films are also investigated. ExperimentalDetermination of reaction rates.-Chemical components and substrate materials used for the Cu deposition experiment basically follow those from ou...

The sticking of product material to injection molding tools is a serious problem, which reduces productivity and reliability. Depositing alloy nitride coatings (TiN, ZrN, CrN, and TiAlCrN) using closed field unbalanced magnetron sputter ion plating and electrodeposition of chromium, and characterizing their surface free energies in the temperature range 20-120 C have led to the development of a non-sticking (with a low surface free energy) coating system for semiconductor IC packaging molding dies. The contact angles of water, diiodomethane and ethylene glycol on the coated surfaces were measured at temperatures in the range 20-120 C using a Dataphysics OCA-20 contact angle analyzer. The surface free energy of the coatings and their components (dispersion and polar) were calculated using the Owens-Wendt geometric mean approach. The surface roughness of these coatings were investigated by atomic force microscopy (AFM). The adhesion force of these coatings were measured using direct tensile pull-off test apparatus. The experimental results revealed that TiAlCrN, CrN and ZrN coatings outperformed Hard-Cr and TiN coatings in terms of anti-adhesion, and thus have the potential as working layers for injection molding industrial equipment, especially in semiconductor IC packaging molding applications.

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