Dry etching properties of methyl-BCN film with C4F8 gas for Cu/low-k interconnection

Methyl-BCN is an attractive low-k material for the fabrication of next generation LSI device system. This paper describes dry etching of methyl-BCN film in order to develop interconnections for future devices. The methyl-BCN films were deposited by plasma-assisted chemical-vapor deposition (PACVD) using tris(dimethylamino)boron (TMAB) gas at 350 °C. We have investigated dry etching properties and mechanism of the methyl-BCN film using C₄F₈ gas with induced coupling plasma (ICP) etching equipment. In this study we used C₄F₈ gas whose atmospheric lifetime is less than one-sixteenth of the conventional CF₄ gas for suppression greenhouse gases. It was found that methyl bonds in the methyl-BCN film can be kept after dry etching, because the peak of C–H (2962 cm^?1) in Fourier transform infrared absorption (FTIR) spectra didn't significantly change after dry etching. X-ray photoelectron spectroscopy (XPS) analysis shows the presence of C–F₂ and C–F₃ bonds just on the methyl-BCN surface after dry etching and no traces of these bonds inside the film. It is observed that intensities of B–N and B–C bonds decrease after dry etching. This suggests that the etching of methyl-BCN films by C₄F₈ gas mainly involves boron desorption.     

金刚石薄膜取向性和后处理对其辐X射响应性能的影响

采用微波等离子体化学气相沉积合成金刚石薄膜,通过优化工艺参数和原位等离子后处理等方法来提高金刚石薄膜的质量和辐射响应灵敏度.制作出三明治结构的辐射剂量计.研究了金刚石薄膜取向性和后处理对X射线辐射响应灵敏度的影响.结果表明:薄膜取向性和后处理对X辐射响应性能有很大影响.提高金刚石薄膜的纯度和取向性是提高X射线响应灵敏度的有效途径.制作的金刚石薄膜辐射剂量计的X射线响应电流与辐射剂量率间有良好的线性关系.在电阻率相近的情况下,[100]取向金刚石薄膜制成的器件X射线响应灵敏度比[111]取向的高,取向度越高,其辐射响应灵敏度也越高.原位氧等离子后处理金刚石薄膜剂量计的X射线响应灵敏度比原位氮、氢等离子后处理的高,薄膜表面金刚石的含量由69.9%提高到93.5%,辐射响应灵敏度较未处理的膜提高1倍以上.     

Plasma surface modification of polyimide for improving adhesion to electroless copper coatings

The influences of oxygen plasma treatment of polyimide (PI) films on the adhesion of electroless copper coatings as well as on the chemical composition of the film surface and the PI surface morphology were investigated. The plasma operating parameters were 1800 W forward power with O₂ flowing at a rate of 300 cm³/min at a pressure of 200 mTorr. The peel strength increased with decreasing plasma treatment temperature. However, extension of the treatment time at higher temperatures had a positive effect on adhesion. A correlation between the enhancement in peel strength and the content of oxygen-containing groups at the PI surface (investigated using XPS) was observed. A change in the morphology as a result of plasma etching was also observed, in the formation of pits in the film surface. The pits ranged from 3 to 6 μm in depth and the diameter varied from 10 to 200 μm. Comparison of the data obtained after plasma treatment with the results of chemical etching in alkaline solutions of permanganate showed approximately the same adhesion increase (to 0.6 kN/m) in both cases. However, chemical etching did not affect the surface morphology and increased the oxygen content at the PI surface less than the plasma treatment.     

Surface modification of low‐density polyethylene (LDPE) film and improvement of adhesion between evaporated copper metal film and LDPE

To improve the interfacial adhesion between evaporated copper film and low‐density polyethylene (LDPE) film, the surface of LDPE films was modified by treating with chromic acid [K₂Cr₂O₇/H₂O/H₂SO₄ (4.4/7.1/88.5)]/oxygen plasma. Chromic‐acid‐etched LDPE was exposed to oxygen plasma to achieve a higher content of polar groups on the LDPE surface. We investigated the effect of the treatment time of chromic acid in the range of 1–60 min at 70°C and oxygen plasma in the range of 30–90 sec on the extent of polar groups created on the LDPE. We also investigated the surface topography of and water contact angle on the LDPE film surface, mechanical properties of the LDPE film, and adhesion strength of the evaporated copper metal film to the LDPE film surface. IR and electron spectroscopy for chemical analysis revealed the introduction of polar groups on the modified LDPE film surface, which exhibited an improved contact angle and copper/LDPE adhesion. The number of polar groups and the surface roughness increased with increasing treatment time of chromic acid/plasma. Water contact angle significantly decreased with increasing treatment time of chromic acid/plasma. Combination treatment of oxygen plasma with chromic acid drastically decreased the contact angle. When the treatment times of chromic acid and oxygen plasma were greater than 10 min and 30 sec, respectively, the contact angle was below 20°. With an increasing treatment time of chromic acid, the tensile strength of the LDPE film decreased, and the film color changed after about 10 min and then became blackened after 30 min. With the scratch test, the adhesion between copper and LDPE was found to increase with an increasing treatment time of chromic acid/oxygen plasma. From these results, we found that the optimum treatment times with chromic acid and oxygen plasma were near 30 min and 30 sec, respectively. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 1677–1690, 2001     

Plasma‐induced surface modification and adhesion enhancement of polypropylene surface

Unoriented (UPP) and biaxially oriented (BOPP) polypropylene films were treated under radio frequency plasma of air, nitrogen, oxygen, and ammonia. Surface modification of polypropylene films was investigated by using surface energy measurement and attenuated total reflection (ATR)‐FTIR spectroscopy. Surface energy of air and nitrogen plasma‐treated polypropylene film increased for shorter treatment time and then decreased and attained an equilibrium value. Such changes in surface energy were not observed for oxygen and ammonia plasma‐treated polypropylene film, which increased to an equilibrium value. ATR‐FTIR studies revealed characteristic differences in the absorption spectra for short‐duration and long‐duration treatments. From the relative intensity change in the C—H stretching vibration, the mechanism of surface chemical reaction could be inferred. Studies regarding the durability of surface modification due to plasma treatment were evaluated by investigating surface energy of samples aged for 2 months. Treated films subjected to peel strength measurement showed improvement in bondability for UPP and BOPP film by hydrophilic surface modification accompanied by surface crosslinking. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 925–936, 2002     

Plasma-polymerized coatings of trimethylsilane deposited on cold-rolled steel substrates Part 2. Effect of deposition conditions on corrosion performance

Trimethyl silane (TMS) plasma-polymerized films were deposited on cold-rolled steel (CRS) under different conditions. The films were characterized by angular-dependent X-ray photoelectron spectroscopy (XPS), Auger electron spectroscopy (AES) and time-of flight secondary ion mass spectrometry (TOFSIMS). The complementary information generated by these surface techniques gave detailed information on the film composition. The corrosion performance of the plasma films was estimated by electrochemical impedance spectroscopy (EIS) and by exposure in a humidity test. All films were Si-based and their composition was a function of the deposition conditions and the plasma cleaning of substrate prior to deposition. A reducing plasma for metal surface treatment resulted in a film with the highest impedance. The plasma film surfaces were highly oxidized. The contact angle was the lowest for plasma films deposited from a mixture of TMS and oxygen and their corrosion performance was the poorest.     

Surface hydrophilization of two polyester films by atmospheric-pressure plasma and ultraviolet excimer light exposures

Polyethylene terephthalate (PET) and polyethylene naphthalate (PEN) films were treated with an atmospheric-pressure plasma (APP) jet and a 172-nm ultraviolet (UV) excimer light in air. The advancing and receding water contact angles on both films decreased after the treatments, especially after APP treatment. After the treatments, the hydrophobic recovery was observed and almost diminished within a week. The dispersive component of the surface free energy of the two polyester films did not change due to the APP and UV exposure, whereas the acid–base component drastically increased after the treatments. The X-ray photoelectron spectroscopy results showed that the polyester film surfaces were oxidized by the treatments. From the AFM images, the topographical change on the film surfaces due to the treatments was clearly observed. It was found that the APP treatment of the PET film prevented the deposition of particulate soils in air due to the decrease in the contact area between the film and the soil particle. Furthermore, the soil release in the aqueous solutions was promoted as a result of the hydrophilization of the polyester films due to the APP treatment.     

Investigation of crystallinity effects on the surface of oxygen plasma treated low density polyethylene using X-ray photoelectron spectroscopy

Plasma treated polymer surface shows rapid hydrophobic recovery after plasma treatment. Surface rearrangement and the hydrophilicity change of low density polyethylene (LDPE) films with different degrees of crystallinity after oxygen plasma treatment were investigated using X-ray photoelectron spectroscopy (XPS) and water contact angle measurements. Since the mobility of polymer chain was restricted in the crystalline region, the chain movement of high crystalline polymer would be reduced. Water contact angles of quenched and annealed LDPE just after plasma treatment were almost same and oxygen contents of quenched LDPE was slightly higher than that of annealed LDPE. However, annealed LDPE showed slower contact angle raise and kept higher oxygen concentration than quenched LDPE with increasing aging time. By deconvolution of carbon XPS spectra, it was observed that major group contributed to decrease of oxygen contents was the hydroxyl groups and hydroxyl groups of quenched LDPE decayed faster than annealed LDPE while other oxygen species kept constant or decreased slightly. Increasing crystallinity reduce the surface rearrangement of polymer chain after plasma treatment.     

Characterization of surface‐modified polyalkanoate films for biomedical applications

Poly(3‐hydroxybutyrate‐co‐3‐hydroxyvalerate) (PHBHV) films prepared by solvent casting were treated with oxygen, argon, and nitrogen radiofrequency‐generated plasmas. The analysis by attenuated total reflectance infrared spectroscopy and X‐ray absorption near edge spectroscopy of modified surfaces showed an increase of hydroxyl and unsaturated groups, compared with unmodified surfaces. Water contact angles decreased after a short time of exposure (<30 s) for all types of plasma. At long exposure times (>30 s), the water contact angles appeared to be independent of treatment time for nitrogen and argon plasmas, whereas they continuously decreased for films treated with oxygen. HaCaT cultures on nontreated and treated PHBHV films showed that short plasma exposures of 10–20 s improve cell attachment to a greater extent than long exposure times habitually used in polymer surface plasma treatment. The film surface topology did not influence cell attachment. These results illustrate the importance of a detailed characterization of the surface physicochemistry in plasma‐modified substrates designed as part of a strategy to optimize specific cell–biomaterial interactions. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Fine characterization of plasma‐polymerized films from a methane/air mixture

The plasma polymerization of methane/air mixtures was performed to produce a hydrophilic film on a substrate, and the obtained films were characterized with ellipsometry, elemental analysis, Fourier transform infrared spectroscopy, X‐ray photoelectron spectroscopy, atomic force microscopy, and contact‐angle measurements. Fourier transform infrared revealed that the structure of the plasma‐polymerized films changed with increasing film thickness; that is, an increase in the film thickness led to an increase in the absorbance ratio of the carbonyl band at 1664 cm^?1 to the methyl band at 1385 cm^?1. Although the contents of nitrogen and oxygen measured by elemental analysis changed with the film thickness, the contact angle and X‐ray photoelectron spectroscopy atomic ratio of the films were independent of it. Nitrogen and oxygen were contained in the bulk more than on the surface of the films. Nitrogen and oxygen were copolymerized with methane, and the properties of the obtained films were similar to those of an amide compound. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 3408–3414, 2006     

Zein film: Effects of dielectric barrier discharge atmospheric cold plasma

Dielectric barrier discharge atmospheric plasma is a novel nonthermal technology for the food and packaging industry. The effects of dielectric barrier discharge plasma on the surface, structural, thermal, and moisture sorption properties of edible zein films have been examined. Plasma treatment increased the surface roughness and equillibrium moisture content of the zein film in a direct relationship with the applied voltage level. No significant difference in the thermal stability of the zein film is also observed after plasma treatment. Dielectric barrier discharge plasma treatments of zein film lead to a change in the protein conformation which is confirmed by X‐ray diffraction and Fourier transform Infrared spectroscopy. The evaluation of films modifications by plasma discharge will contribute to enhance the in‐package decontamination studies of food products by plasma. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40803.     

Surface modification of aromatic polyamide film by remote oxygen plasma

Surface modification of poly(p-phenylene terephthalamide) (PPTA) film by a remote oxygen plasma treatment has been investigated from a viewpoint of comparison with a direct oxygen plasma treatment. We call the modification procedure in a space far away from the oxygen plasma zone “the remote oxygen plasma treatment,” and the modification procedure in a space just in the oxygen plasma zone (a conventional oxygen plasma treatment) “the direct oxygen plasma treatment.” In a space far away from the plasma zone, oxygen radicals rather than electrons and oxygen ions are predominant, and the PPTA film can be modified by the remote oxygen plasma treatment into a hydrophilic surface without heavy degradation of the PPTA film. The PPTA film surfaces modified by the remote oxygen plasma treatment were analyzed with contact angle measurement, scanning microscopy, atomic force microscopy, and X-ray photoelectron spectroscopy. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 64: 831–840, 1997     

Preparation of oxygen gas barrier polypropylene films by deposition of SiOx films plasma‐polymerized from mixture of tetramethoxysilane and oxygen

Silicon oxide (SiOx) film deposition on the surface of oriented poly(propylene) (OPP) films was done to form a new oxygen gas barrier material using plasma polymerization of the tetramethoxysilane (TMOS)/O₂ mixture. The SiOx film deposition on OPP films never improved oxygen gas barrier properties. The inefficacy of the SiOx deposition was due to poor adhesion at the interface between the deposited SiOx and OPP films and also to the formation of cracks in the deposited SiOx film. If prior to the SiOx film deposition surface modification of OPP films was done by a combination of the argon plasma treatment and TMOS coupling treatment, this contributed effectively to strong adhesion leading to success in the SiOx deposition on the OPP film surface, and then the oxygen gas barrier ability was improved. The oxygen permeation rate through the SiOx‐deposited OPP film was decreased from 2230 to 37–52 cm³/m²/day/atm, which was comparable to that of poly(vinylidene chloride), 55 cm³/m²/day/atm at a film thickness of 11 μm. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 78: 2389–2397, 2000     

Characterisation of flame retardant plasma polymer deposited BOPP film

Abstract

Flame retardancy of polypropylene films was studied by plasma polymerisation technique. The surface of BOPP film was modified by boron containing plasma polymers at different plasma conditions. Plasma polymer coated polypropylene films were examined by flame retardancy test (limiting oxygen index, LOI) and TGA. Boron containing plasma polymer deposition on the film surface showed an improvement of flame retardancy. Furthermore, TGA thermograms pointed out that the first degradation temperature of treated polypropylene film was increased from 331 to 396°C, and the second degradation temperature was shifted from 401 to 455°C. Also, the plasma polymers were characterised by FTIR spectroscopy and XPS. According to XPS results, the BOPP surfaces treated with TMB showed significant difference in the composition with respect to the untreated sample. The FTIR spectra of plasma polymers obtained indicated that when the treatment time was increased to 60 min with a constant discharge power at 80 W, the absorption intensities of all the functional groups increased. As a result, boron containing plasma polymer treatment was found to be an effective method in enhancing the flame retardancy of BOPP film.     

氮化硅薄膜生长随时间演化过程及其特性研究

氮化硅SiN_x薄膜凭借介电常数高和稳定性好的特点而被广泛应用于光电器件中,但薄膜的厚度对器件的性能有重要影响。针对此问题采用等离子体化学气相沉积技术,以高纯NH₃、N₂和SiH₄为反应气体,优化其他沉积参数,通过改变沉积时间来生长SiN_x薄膜。用X射线衍射谱(XRD),紫外-可见光光谱(UV-VIS)、傅里叶变换红外光谱(FTIR)和扫描电镜(SEM)对薄膜结构进行表征,详细研究了沉积时间与薄膜厚度的关系以及沉积时间对薄膜性能的影响。试验结果表明:所制备的样品为非晶SiN_x薄膜结构,薄膜厚度随沉积时间均匀增加;薄膜折射率随沉积时间的增加而增大,光学带隙基本不随时间变化。SEM测试结果表明,随着沉积时间增加,薄膜致密性与均匀性越来越好,氧含量也越来越少,说明薄膜致密性提高可以有效阻挡O原子进入薄膜,阻止后氧化现象的发生。     

Surface modification of poly(aryl ether ether ketone) film by remote oxygen plasma

Surface modification of poly(aryl ether ether ketone) (PEEK) film surfaces by oxygen plasma treatment was investigated. Two procedures, the direct plasma treatment and the remote oxygen plasma treatment, were used as oxygen plasma treatments, and the efficiency of the hydrophilic modification was discussed. The direct and remote oxygen plasma treatments lead to degradation of the PEEK film as well as hydrophilic surface modification. The degradation disturbs the surface modification. The remote oxygen plasma treatment rather than the direct oxygen plasma is suitable for the hydrophilic surface modification of the PEEK film. The remote oxygen plasma treatment at 10 W for 60 s forms predominantly C—O groups rather than C=O groups as an oxygen-containing group on the PEEK surface and gives a highly hydrophilic surface with a contact angle of 44 degrees. © 1998 John Wiley & Sons, Inc. J Appl Polm Sci 68:271–279, 1998     

Simultaneous graft copolymerization of 2‐hydroxyethyl methacrylate and acrylic acid onto polydimethylsiloxane surfaces using a two‐step plasma treatment

Acrylic acid (AAc) and 2‐hydroxyethyl methacrylate (HEMA) mixtures were simultaneously grafted onto the surfaces of polydimethylsiloxane (PDMS) films using a two‐step oxygen plasma treatment (TSPT). The first step of this method includes: oxygen plasma pretreatment of the PDMS films, immersion in HEMA/AAc mixtures, removal from the mixtures, and drying. The second step was carried out by plasma copolymerization of preadsorbed reactive monomers on the surfaces of dried pretreated films. The effects of pretreatment and polymerization time length, monomer concentration, and ratio on peroxide formation and graft amount were studied. The films were characterized by attenuated total reflection Furrier transformer infrared (ATR‐FTIR) spectroscopy, scanning electron microscopy (SEM), atomic force microscopy (AFM), zeta potential, surface tension, and water contact angle measurements. The ATR‐FTIR spectrum of the modified film after alkaline treatment showed the two new characteristic bands of PHEMA and PAAc. Both increase the polar part of surface tension (γ_p) after grafting and the evaluation of surface charge at pH 1.8, 7, and 12 confirmed the presence of polar groups on the surface of grafted films with a mixture of HEMA/AAc. Morphological studies using both AFM and SEM evaluation illustrated various amounts of grafted copolymer on the surface of PDMS films. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007     

Oxygen plasma modification of poly(3‐hydroxybutyrate‐co‐3‐hydroxyvalerate) film surfaces for tissue engineering purposes

Plasma glow‐discharge application is known as a technique to coat or modify the surfaces of various materials. In this study, the influence of oxygen rf‐plasma treatment on surface and bulk properties of a biological polyester, poly(3‐hydroxybutyrate‐co‐3‐hydroxyvalerate), were studied by determining water content and water contact angle, and by using X‐ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). The plasma‐treated films absorbed more water than the untreated film, and the absorbance increased with the total power applied. The water contact angles decreased and O/C atomic ratio increased on treatment, indicating that the material became more hydrophilic due to increases in the oxygen‐containing functional groups on the surface of the polymer. A direct relation could be observed when the O/C ratio was plotted against the total power applied (treatment duration × treatment power). SEM revealed a visual record of surface modification, the extent of which increased with increased total power. It was thus possible to alter the surface chemistry and relevant properties of the polymer film using oxygen plasma as a tool. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 1285–1289, 2003     

Atomic force microscopy analysis of cellulose triacetate surface modified in low temperature argon plasma and its adhesion behavior

The surface of cellulose triacetate (CTA) film was modified with gaseous plasma of several discharge power in the presence of Argon (Ar) gas at 0.5 torr pressure. After gas plasma etching, the surface structure of the films is analyzed by atomic force microscopy (AFM) and measured with peel strength. Furthermore, the wetting properties of the CTA film treated with Ar plasma are studied by contact angle measurement. Peel strength after plasma treatment was increased with increasing plasma treatment time. However, treatments of plasma greater than 7 min did not find an additional increase in peel strength, similarly to roughness and morphological changes of AFM. The water contact angle decreased for an initial treatment time due to the improved wettability of the film, but showed an increasing trend for a higher treatment time (7 min). These results show that Ar plasma treatment is a convenient tool for improving the adhesive properties of CTA film. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 3963–3971, 2006     

Characterization of BCN film after wet process for interconnection integration

In this study, we investigate the influence of the wet chemical processes involved in the chemical treatment of boron carbon nitride (BCN) films deposited by plasma-assisted chemical vapor deposition (PACVD). BCN film is expected to be a low dielectric constant (low-K) material useful in fabricating future generation LSI devices. BCN film with less than 10% oxygen was hardly etched. The etching rate of the BCN film with an oxygen composition ratio more than 10% depends on the pH of the solution. The relationship between the film etching rate and the atomic bonds in BCN film is also investigated using XPS and FTIR. It was found that the BCN films without C–O and B–O bonds are not etched by acid and alkaline solutions. Therefore, suppression of oxygen concentration in the BCN film is important for LSI integration.