Papers by Keyword: SPM

Abstract: The semiconductor industry is a significant consumer of water and chemicals. In particular, water is a valuable resource, and its efficient use is crucial to ensure availability for future generations. By implementing measures to reduce water and chemical consumption, the semiconductor industry can minimize its environmental footprint and contribute to sustainability efforts. Technology for the recycling of unused hot ultrapure water (H-UPW), ozonated water and reclaimed sulfuric acid-hydrogen peroxide mixtures (SPM) has been developed and installed in high-volume manufacturing (HVM) semiconductor manufacturing facilities. This paper presents an overview of the technology and expected savings in water, sulfuric acid and energy consumption from the implementation of these technologies.

Abstract: A large amount of chemicals and ultrapure water (UPW) have been used for wet cleaning process in the semiconductor manufacturing processes. One of the most commonly used cleaning solutions is Sulfuric acid (H₂SO₄) and Hydrogen Peroxide (H₂O₂) Mixture (SPM). It is used for resist stripping, etc. on a silicon wafer. As the cleaning process increases, so does the amount of chemicals used with the recent miniaturization. As a result, wastewater will also increase, and there are concerns about the impact on the environmental aspects. The technologies to reduce H₂SO₄ [1, 2] have been developed, but its consumption still persists. Therefore, in this paper, we developed high concentrated O₃-water without using H₂SO₄, and conducted a resist stripping test verify its effectiveness as an alternative to SPM.

Abstract: Photoresist after implantation is commonly removed either by wet chemical dissolution with sulfuric acid, or by dry ash stripping followed with a wet cleaning. To prevent any photoresist residues, sulfuric acid is still conserved in post ash cleans as additional safety. However, by ensuring sufficient over ash time, SPM (Sulfuric acid Peroxide hydrogen Mixture) chemical need becomes less essential. This paper reevaluates the benefit of SPM after dry ash stripping regarding the environmental context. The advantages of dry ash stripping with clean, compared to wet stripping are outlined. The study introduces prior analyses on defectivity and material consumption. Finally, device matching and yield stability, defined as the main success criteria, are described.

Abstract: The definition of sub-20 nm electronic devices for the newest generation of smart phones, computer and automotive is calling for very innovative FEOL wet chemical cleans. The electronic properties are very sensitive, in respect of the surface morphology on a Si-wafer. Most of the modern wet cleans are based on the RCA-clean [1]. Innovative cleans, like for example the IMEC-clean [2] and modified RCA clean were developed, using ozone-DIW mixture (O₃-DIW), in order to improve the cleaning performance [3], [4]. Since several years electrolyzed water (EW) is used in semiconductor manufacturing [5]. An electrochemical reaction is induced by an electrode and a small amount of ammonia hydroxide (NH₄OH) or ammonia sulfate and DIW [7].

Abstract: Air quality indices are used for local and regional air quality management in many metro cities of the world. The present investigation was carried out to find the significance of air pollutant concentrations at commercial areas of Chennai. Suspended Particulate Matter (SPM), Respirable Suspended Particulate Matter (RSPM), Sulphur dioxide (SO2) and Oxides of nitrogen (NOX) were analyzed over two sites namely T.Nagar and Kilpauk in Chennai. Both the sampling stations selected are located in commercial areas. Several concepts and indicators exist to measure and rank the urban areas in terms of their socio-economic infrastructure and environment related parameters. In this paper an air quality index (AQI) considering the combined level of three criteria pollutants (oxides of nitrogen, sulphur dioxide, and Respirable suspended particulate matter ) is proposed.

Abstract: This study discusses changes in the value of fractal parameters determined based on functions of structure S(t), generated in different directions of anisotropy of the examined surfaces. The analyzed material consisted of AFM calibration standards TGT1, PG and TGZ1 which were used as models of strongly isotropic and anisotropic surfaces. The topography of the examined surfaces was imaged by atomic force microscopy. The obtained results indicate that all surfaces can be described mathematically to identify fractal parameters in any anisotropic direction.

Abstract: Widely used engineered nanomaterials (NMs) display unique properties that may have impact on human health, and thus require a reliable evaluation of their potential cytotoxicity. There is a continuing need for real-time imaging techniques capable of studying the interactions between NMs and living alveolar epithelial cells under physiological conditions. A new developed noninvasive HPICM is designed for continuous high-resolution topographic imaging of living cells, which makes it an ideal tool to study NMs cytotoxicity in living alveolar epithelia by performing reliable repetitive scanning. In this review, we concisely introduced the operation principle of HPICM and its applications to real-time investigation of engineered NMs cytotoxicity in living alveolar epithelia. Published results demonstrate that non-contact HPICM combined with patch-clamp has the potential to become a powerful microscopy for real-time studies of NM-cell interactions under physiological conditions.

Abstract: A series of fluorocarbon films were deposited on glass substrates by Pulsed Plasma Thruster. The effects of deposited angle on chemical structure and surface morphology of these films were investigated using X-ray photoelectron spectroscopy (XPS) and scanning probe microscope (SPM). XPS data imply various carbon-related chemical components present on the surface of the deposited films are strongly impacted by the deposited angle. AFM measurements show that the increase in deposited angle can smoothen the surface morphology and decrease the RMS roughness. Changes in density of the neutral particle and flux of ions that reach the surface affect the formation of fluorocarbon clusters in the films and reduce surface roughness.

Abstract: It is known that resist removal capability of SPM gradually deteriorates during the stripping process. The deterioration is theoretically explained to be the decrease in the concentration of sulfuric acid. On the contrary, in the case of electrolyzed sulfuric acid method, both concentrations of sulfuric acid and of peroxodisulfuric acid produced by electrolysis are kept constant, so that the resist removal capability is maintained for a long term even without addition of hydrogen peroxide. It is proved that resist patterned on φ300mm wafers and implanted at 1E14 atoms/cm² can be removed using electrolyzed sulfuric acid solution without ashing process.

Abstract: Continuous high-resolution observations of cell membrane would greatly aid the elucidation of the relationship between structure and function and facilitate the study of physiological processing in cell biology. However, high-resolution studying living neuron membrane structures and its functions is still a challenge in current nanobiology. The new developed Hoping Probe Ion Conductance Microscopy (HPICM) is designed for non-contact continuous high-resolution topographic imaging of living cells under physiological conditions. In this review, we concisely introduced the basic operation principle of HPICM and its applications in high spatial resolution imaging of two living neuron cell models, N-type SK-N-SH cells and NGF-differentiated sympathetic neuron-like PC12 cells. Combining HPICM with patch-clamp technique, we further investigated the functional ion-channel of under-differentiated neuron-like PC12 cells and demonstrated that NGF treatment promoted the outgrowth of neurites and increased the activity of TTX-sensitive sodium channel. All these results demonstrate that HPICM combined with patch-clamp technique offers high-resolution topographic imaging of living neurons with non-contact — making HPICM an ideal high-resolution imaging technique not to interact/interfere with living neurons during image acquisition, and provides detailed information about the relationship between membrane structures and ion-channel functions of living neurons at the same time, which has the potential to become a powerful microscopy for in-depth researching in neural nanobiology.