Dr. Bangtao Chen Profile

Dr. Bangtao Chen

at Institute of Microelectronics

SPIE Involvement:

Author

Publications (7)

Proceedings Article | 5 January 2009 Paper

Low-stress PECVD amorphous silicon carbide (α-SiC) layers for biomedical application

Jiashen Wei, Bangtao Chen, Daniel Poenar, Yong Yeow Lee, Ciprian Iliescu

Proceedings Volume 7269, 72690C (2009) https://doi.org/10.1117/12.810883

KEYWORDS: Plasma enhanced chemical vapor deposition, Silicon carbide, Silicon, Semiconducting wafers, Refractive index, Biomedical optics, Etching, Ions, Crystals, Amorphous silicon

Read Abstract +

Proceedings Article | 30 December 2008 Paper

Development of thick film PECVD amorphous silicon with low stress for MEMS applications

Bangtao Chen, Francis Tay, Ciprian Iliescu

Proceedings Volume 7269, 72690M (2008) https://doi.org/10.1117/12.810441

KEYWORDS: Glasses, Plasma enhanced chemical vapor deposition, Microelectromechanical systems, Argon, Wet etching, Photomasks, Silicon carbide, Semiconducting wafers, Photoresist materials, Etching

Read Abstract +

Proceedings Article | 30 December 2008 Paper

Microneedles array with biodegradable tips for transdermal drug delivery

Ciprian Iliescu, Bangtao Chen, Jiashen Wei, Francis Tay

Proceedings Volume 7270, 72700M (2008) https://doi.org/10.1117/12.810692

KEYWORDS: Skin, Silicon, Photoresist materials, Reactive ion etching, Diffusion, In vitro testing, Photomasks, Deep reactive ion etching, Etching, Scanning electron microscopy

Read Abstract +

Proceedings Article | 20 December 2006 Paper

Adhesive wafer-to-wafer bonding using contact imprinting

Liming Yu, Ah Ju Pang, Bangtao Chen, Francis Tay, Ciprian Iliescu

Proceedings Volume 6415, 64151I (2006) https://doi.org/10.1117/12.696544

KEYWORDS: Semiconducting wafers, Adhesives, Wafer bonding, Photoresist materials, Silicon, Microfluidics, Glasses, Dielectrophoresis, Nanotechnology, Fabrication

Read Abstract +

Proceedings Article | 20 December 2006 Open Access

Low-stress silicon nitride layers for MEMS applications

Ciprian Iliescu, Jiashen Wei, Bangtao Chen, Poh Lam Ong, Francis E. Tay

Proceedings Volume 6415, 64150L (2006) https://doi.org/10.1117/12.696350

KEYWORDS: Silicon, Plasma, Semiconducting wafers, Stem cells, Plasma enhanced chemical vapor deposition, Gases, Etching, Microelectromechanical systems, Wet etching, Ions

Read Abstract +

DOWNLOAD PAPER

Proceedings Article | 19 January 2006 Paper

A new fabrication process of silicon nanotips: NERCOM

Francis Tay, Ciprian Iliescu, Guolin Xu, Bangtao Chen, Marioara Avram

Proceedings Volume 6036, 603608 (2006) https://doi.org/10.1117/12.638516

KEYWORDS: Photoresist materials, Photomasks, Silicon, Reactive ion etching, Nanolithography, Plasma etching, Etching, Semiconducting wafers, Thermoelectric materials, Oxidation

Read Abstract +

Proceedings Article | 29 December 2005 Paper

Characterization of deep wet etching of glass

Ciprian Iliescu, Bangtao Chen, Francis Tay, Guolin Xu, Jianmin Miao

Proceedings Volume 6037, 60370A (2005) https://doi.org/10.1117/12.638521

KEYWORDS: Etching, Glasses, Photomasks, Wet etching, Semiconducting wafers, Silicon, Photoresist materials, Amorphous silicon, Gold, Annealing

Read Abstract +

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 Al₂O₃ 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 N₂ 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).

Showing 5 of 7 publications

View contact details

UPDATE YOUR PROFILE

Is this your profile? Update it now.

Sign into your SPIE.org account

Don’t have a profile and want one?

Create an account on SPIE.org

Keywords/Phrases

Search In:

Publication Years