The Experts below are selected from a list of 19758 Experts worldwide ranked by ideXlab platform
James H. Edgar - One of the best experts on this subject based on the ideXlab platform.
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Wet Etching of GaN, AlN, and SiC : a review
Materials Science and Engineering: R: Reports, 2005Co-Authors: D. Zhuang, James H. EdgarAbstract:Abstract The Wet Etching of GaN, AlN, and SiC is reviewed including conventional Etching in aqueous solutions, electrochemical Etching in electrolytes and defect-selective chemical Etching in molten salts. The mechanism of each Etching process is discussed. Etching parameters leading to highly anisotropic Etching, dopant-type/bandgap selective Etching, defect-selective Etching, as well as isotropic Etching are discussed. The etch pit shapes and their origins are discussed. The applications of Wet Etching techniques to characterize crystal polarity and defect density/distribution are reviewed. Additional applications of Wet Etching for device fabrication, such as producing crystallographic etch profiles, are also reviewed.
Ciprian Iliescu - One of the best experts on this subject based on the ideXlab platform.
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Strategies in deep Wet Etching of Pyrex glass
Sensors and Actuators A-physical, 2007Co-Authors: Ciprian Iliescu, Francis E. H. Tay, Jianmin MiaoAbstract:This paper establishes the strategies for deep Wet Etching of one of the most common glasses: Pyrex. There are two way for increasing the etch depth: increasing the etch rate or increasing the resistance of the mask in the Etching solution. The paper analyzes the methods for increasing the glass etch rate in HF solutions: annealing, concentration, ultrasonic agitation and temperature. The generation of the defects is investigated. The main factors that affect the degradation of the mask are: type, value and gradient of the residual stress and the hydrophilicity of the surface. Cr/Au mask is used for illustration. A new method for deep Wet Etching of glass using Cr/Au mask and photoresist is established. The result of this method is the best thus far as reported in the literature: 85 min deep Wet Etching in HF 49% which is equivalent to Etching of more than 500 μm deep in the Pyrex glass material.
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Characterization of deep Wet Etching of glass
Device and Process Technologies for Microelectronics MEMS and Photonics IV, 2005Co-Authors: Ciprian Iliescu, Francis E. H. Tay, Bangtao Chen, Jianmin MiaoAbstract:This paper presents a characterization of Wet Etching of glass in HF-based solutions with a focus on Etching rate, masking layers and quality of the generated surface. The first important factor that affects the deep Wet Etching process is the glass composition. The presence of oxides such as CaO, MgO or Al 2 O 3 that give insoluble products after reaction with HF can generate rough surface and modify the Etching rate. A second factor that influences especially the etch rate is the annealing process (560°C / 6 hours in N 2 environment). For annealed glass samples an increase of the etch rate with 50-60% was achieved. Another important factor is the concentration of the HF solution. For deep Wet Etching of Pyrex glass in hydrofluoric acid solution, different masking layers such as Cr/Au, PECVD amorphous silicon, LPCVD polysilicon and silicon carbide are analyzed. Detailed studies show that the stress in the masking layer is a critical factor for deep Wet Etching of glass. A low value of compressive stress is recommended. High value of tensile stress in the masking layer (200-300 MPa) can be an important factor in the generation of the pinholes. Another factor is the surface hydrophilicity. A hydrophobic surface of the masking layer will prevent the Etching solution from flowing through the deposition defects (micro/nano channels or cracks) and the generation of pinholes is reduced. The stress gradient in the masking layer can also be an important factor in generation of the notching defects on the edges. Using these considerations a special multilayer masks Cr/Au/Photoresist (AZ7220) and amorphous silicon/silicon carbide/Photoresist were fabricated for deep Wet Etching of a 500 μm and 1mm-thick respectively Pyrex glass wafers. In both cases the Etching was performed through wafer. From our knowledge these are the best results reported in the literature. The quality of the generated surface is another important factor in the fabrication process. We notice that the roughness of generated surface can be significantly improved by adding HCl in HF solution (the optimal ratio between HF (49%) and HCl (37%) was 10/1).
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Characterization of masking layers for deep Wet Etching of glass in an improved HF/HCl solution
Surface & Coatings Technology, 2004Co-Authors: Ciprian Iliescu, Francis E. H. Tay, Jianmin Miao, Ji Jing, Tietun SunAbstract:Abstract The paper presents a solution for improving the quality of the surface generated during deep Wet Etching of glass using an HF (49%)/HCl (37%) solution in a volumetric ratio 10:1. Pyrex glass (Corning 7740) and soda lime glass were analyzed. In addition, the characterization of the main masking layers, including photoresist, amorphous silicon, polysilicon and Cr/Au for deep Wet Etching in the optimal solution, is described.
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Wet Etching of glass
CAS 2005 Proceedings. 2005 International Semiconductor Conference 2005., 1Co-Authors: Ciprian Iliescu, Francis E. H. TayAbstract:The purpose of this paper is to find ways to Improve the Wet Etching techniques used for glass Etching. Essential elements of glass Wet Etching process such as: influence of glass composition, Etching rate, influence of the residual stress in the masking layer, characterization of the main masking materials, the quality of surface generated using Wet Etching process are analyzed. As a result of this analysis an improved technique for deep Wet Etching of glass is proposed. A 500-/spl mu/m thick Pyrex glass wafer was etched through using a Cr/Au and photoresist mask, from our knowledge this is the best result reported. For an improved surface an optimal solution HF/HCl (10:1) was established for Pyrex and soda lime glasses. The developed techniques are currently used for fabrication of microfluidic devices on glass.
Jianmin Miao - One of the best experts on this subject based on the ideXlab platform.
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Strategies in deep Wet Etching of Pyrex glass
Sensors and Actuators A-physical, 2007Co-Authors: Ciprian Iliescu, Francis E. H. Tay, Jianmin MiaoAbstract:This paper establishes the strategies for deep Wet Etching of one of the most common glasses: Pyrex. There are two way for increasing the etch depth: increasing the etch rate or increasing the resistance of the mask in the Etching solution. The paper analyzes the methods for increasing the glass etch rate in HF solutions: annealing, concentration, ultrasonic agitation and temperature. The generation of the defects is investigated. The main factors that affect the degradation of the mask are: type, value and gradient of the residual stress and the hydrophilicity of the surface. Cr/Au mask is used for illustration. A new method for deep Wet Etching of glass using Cr/Au mask and photoresist is established. The result of this method is the best thus far as reported in the literature: 85 min deep Wet Etching in HF 49% which is equivalent to Etching of more than 500 μm deep in the Pyrex glass material.
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Characterization of deep Wet Etching of glass
Device and Process Technologies for Microelectronics MEMS and Photonics IV, 2005Co-Authors: Ciprian Iliescu, Francis E. H. Tay, Bangtao Chen, Jianmin MiaoAbstract:This paper presents a characterization of Wet Etching of glass in HF-based solutions with a focus on Etching rate, masking layers and quality of the generated surface. The first important factor that affects the deep Wet Etching process is the glass composition. The presence of oxides such as CaO, MgO or Al 2 O 3 that give insoluble products after reaction with HF can generate rough surface and modify the Etching rate. A second factor that influences especially the etch rate is the annealing process (560°C / 6 hours in N 2 environment). For annealed glass samples an increase of the etch rate with 50-60% was achieved. Another important factor is the concentration of the HF solution. For deep Wet Etching of Pyrex glass in hydrofluoric acid solution, different masking layers such as Cr/Au, PECVD amorphous silicon, LPCVD polysilicon and silicon carbide are analyzed. Detailed studies show that the stress in the masking layer is a critical factor for deep Wet Etching of glass. A low value of compressive stress is recommended. High value of tensile stress in the masking layer (200-300 MPa) can be an important factor in the generation of the pinholes. Another factor is the surface hydrophilicity. A hydrophobic surface of the masking layer will prevent the Etching solution from flowing through the deposition defects (micro/nano channels or cracks) and the generation of pinholes is reduced. The stress gradient in the masking layer can also be an important factor in generation of the notching defects on the edges. Using these considerations a special multilayer masks Cr/Au/Photoresist (AZ7220) and amorphous silicon/silicon carbide/Photoresist were fabricated for deep Wet Etching of a 500 μm and 1mm-thick respectively Pyrex glass wafers. In both cases the Etching was performed through wafer. From our knowledge these are the best results reported in the literature. The quality of the generated surface is another important factor in the fabrication process. We notice that the roughness of generated surface can be significantly improved by adding HCl in HF solution (the optimal ratio between HF (49%) and HCl (37%) was 10/1).
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Characterization of masking layers for deep Wet Etching of glass in an improved HF/HCl solution
Surface & Coatings Technology, 2004Co-Authors: Ciprian Iliescu, Francis E. H. Tay, Jianmin Miao, Ji Jing, Tietun SunAbstract:Abstract The paper presents a solution for improving the quality of the surface generated during deep Wet Etching of glass using an HF (49%)/HCl (37%) solution in a volumetric ratio 10:1. Pyrex glass (Corning 7740) and soda lime glass were analyzed. In addition, the characterization of the main masking layers, including photoresist, amorphous silicon, polysilicon and Cr/Au for deep Wet Etching in the optimal solution, is described.
D. Zhuang - One of the best experts on this subject based on the ideXlab platform.
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Wet Etching of GaN, AlN, and SiC : a review
Materials Science and Engineering: R: Reports, 2005Co-Authors: D. Zhuang, James H. EdgarAbstract:Abstract The Wet Etching of GaN, AlN, and SiC is reviewed including conventional Etching in aqueous solutions, electrochemical Etching in electrolytes and defect-selective chemical Etching in molten salts. The mechanism of each Etching process is discussed. Etching parameters leading to highly anisotropic Etching, dopant-type/bandgap selective Etching, defect-selective Etching, as well as isotropic Etching are discussed. The etch pit shapes and their origins are discussed. The applications of Wet Etching techniques to characterize crystal polarity and defect density/distribution are reviewed. Additional applications of Wet Etching for device fabrication, such as producing crystallographic etch profiles, are also reviewed.
Francis E. H. Tay - One of the best experts on this subject based on the ideXlab platform.
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Strategies in deep Wet Etching of Pyrex glass
Sensors and Actuators A-physical, 2007Co-Authors: Ciprian Iliescu, Francis E. H. Tay, Jianmin MiaoAbstract:This paper establishes the strategies for deep Wet Etching of one of the most common glasses: Pyrex. There are two way for increasing the etch depth: increasing the etch rate or increasing the resistance of the mask in the Etching solution. The paper analyzes the methods for increasing the glass etch rate in HF solutions: annealing, concentration, ultrasonic agitation and temperature. The generation of the defects is investigated. The main factors that affect the degradation of the mask are: type, value and gradient of the residual stress and the hydrophilicity of the surface. Cr/Au mask is used for illustration. A new method for deep Wet Etching of glass using Cr/Au mask and photoresist is established. The result of this method is the best thus far as reported in the literature: 85 min deep Wet Etching in HF 49% which is equivalent to Etching of more than 500 μm deep in the Pyrex glass material.
-
Characterization of deep Wet Etching of glass
Device and Process Technologies for Microelectronics MEMS and Photonics IV, 2005Co-Authors: Ciprian Iliescu, Francis E. H. Tay, Bangtao Chen, Jianmin MiaoAbstract:This paper presents a characterization of Wet Etching of glass in HF-based solutions with a focus on Etching rate, masking layers and quality of the generated surface. The first important factor that affects the deep Wet Etching process is the glass composition. The presence of oxides such as CaO, MgO or Al 2 O 3 that give insoluble products after reaction with HF can generate rough surface and modify the Etching rate. A second factor that influences especially the etch rate is the annealing process (560°C / 6 hours in N 2 environment). For annealed glass samples an increase of the etch rate with 50-60% was achieved. Another important factor is the concentration of the HF solution. For deep Wet Etching of Pyrex glass in hydrofluoric acid solution, different masking layers such as Cr/Au, PECVD amorphous silicon, LPCVD polysilicon and silicon carbide are analyzed. Detailed studies show that the stress in the masking layer is a critical factor for deep Wet Etching of glass. A low value of compressive stress is recommended. High value of tensile stress in the masking layer (200-300 MPa) can be an important factor in the generation of the pinholes. Another factor is the surface hydrophilicity. A hydrophobic surface of the masking layer will prevent the Etching solution from flowing through the deposition defects (micro/nano channels or cracks) and the generation of pinholes is reduced. The stress gradient in the masking layer can also be an important factor in generation of the notching defects on the edges. Using these considerations a special multilayer masks Cr/Au/Photoresist (AZ7220) and amorphous silicon/silicon carbide/Photoresist were fabricated for deep Wet Etching of a 500 μm and 1mm-thick respectively Pyrex glass wafers. In both cases the Etching was performed through wafer. From our knowledge these are the best results reported in the literature. The quality of the generated surface is another important factor in the fabrication process. We notice that the roughness of generated surface can be significantly improved by adding HCl in HF solution (the optimal ratio between HF (49%) and HCl (37%) was 10/1).
-
Characterization of masking layers for deep Wet Etching of glass in an improved HF/HCl solution
Surface & Coatings Technology, 2004Co-Authors: Ciprian Iliescu, Francis E. H. Tay, Jianmin Miao, Ji Jing, Tietun SunAbstract:Abstract The paper presents a solution for improving the quality of the surface generated during deep Wet Etching of glass using an HF (49%)/HCl (37%) solution in a volumetric ratio 10:1. Pyrex glass (Corning 7740) and soda lime glass were analyzed. In addition, the characterization of the main masking layers, including photoresist, amorphous silicon, polysilicon and Cr/Au for deep Wet Etching in the optimal solution, is described.
-
Wet Etching of glass
CAS 2005 Proceedings. 2005 International Semiconductor Conference 2005., 1Co-Authors: Ciprian Iliescu, Francis E. H. TayAbstract:The purpose of this paper is to find ways to Improve the Wet Etching techniques used for glass Etching. Essential elements of glass Wet Etching process such as: influence of glass composition, Etching rate, influence of the residual stress in the masking layer, characterization of the main masking materials, the quality of surface generated using Wet Etching process are analyzed. As a result of this analysis an improved technique for deep Wet Etching of glass is proposed. A 500-/spl mu/m thick Pyrex glass wafer was etched through using a Cr/Au and photoresist mask, from our knowledge this is the best result reported. For an improved surface an optimal solution HF/HCl (10:1) was established for Pyrex and soda lime glasses. The developed techniques are currently used for fabrication of microfluidic devices on glass.
