Ultra Precision Grinding of Wafer Scale

Abstract:

Manufacturing moulds for the wafer-scale replication of precision glass optics sets new demands in terms of grinding tool lifetime and the processes to be applied. This paper will present different approaches to grinding processes and kinematics to machine wafer-scale tungsten carbide moulds with diameters of up to 100 mm and more than 100 single aspheric cavities, each featuring form accuracies in the micron range. The development of these processes will be described and advantages and disadvantages of the approaches derived from practical tests performed on an ultra precision grinding machine (Moore Nanotech 350FG) will be discussed. Finally, a comparison between the developed processes is made where achieved form accuracies and surface topography are analyzed.

• Periodical: Key Engineering Materials (Volume 516)
• Pages: 257-262
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.516.257
• Online since: June 2012
• Authors: Martin Hünten, Fritz Klocke, Olaf Dambon, Benjamin Bulla
• Keywords: Mould, Precision Glass Moulding, Tungsten Carbide, Ultra Precision Grinding, Wafer Level

References

[1] T.G. Bifano, Ductile Regime Grinding Of Brittle Materials, PhD Thesis, North Carolina State University, (1988).

[2] D. Grimme, K. Rickens, Q. Zhao, C. Heinzel, Dressing of coarse-grained diamond wheels for ductile machining of brittle materials, Towards Synthesis of Micro-/Nanosystems B7 (2007) 305-307.

DOI: 10.1007/1-84628-559-3_53

[3] K. Liu, X.P. Li, Ductile cutting of tungsten carbide, J. Mater. Process. Technol. 113 (2001) 348-354.

[4] K. Liu, X.P. Li, M. Rahman, X.D. Liu, CBN tool wear in ductile cutting of tungsten carbide, Wear 255 (2003) 1344-1351.

DOI: 10.1016/s0043-1648(03)00061-9

[5] H. Suzuki et al., Study on precision grinding of micro aspherical surface: effects of tool errors on workpiece form accuracies and its compensation methods, J. Jpn Soc. Prec. Eng. 65 (1999) l401-405.

[6] W.K. Chen, T. Kuriyagawa, H. Huang, H. Ono, M. Saeki, K. Syoji, A novel form error compensation technique for tungsten carbide mould insert machining utilizing parallel grinding technology, Key Eng. Mat. 257–258 (2004) 141-146.

DOI: 10.4028/www.scientific.net/kem.257-258.141

[7] Y. Yamamoto, H. Suzuki, T. Onishi, T. Okino, T. Moriwaki, Precision grinding of microarray lens molding die with 4-axes controlled microwheel, Sci. Tech. Adv. Mat. 8 (2007) 173-176.

DOI: 10.1016/j.stam.2007.02.007

[8] H. Suzuki, T. Moriwaki, Y. Yamamoto, Y. Goto Precision Cutting of Aspherical Ceramic Molds with Micro PCD Milling Tool, CIRP Ann – Manuf. Tech. 56 (2007) 131-134.

DOI: 10.1016/j.cirp.2007.05.033

[9] W. Boehlke: Hartmetall - ein moderner Hochleistungswerkstoff, Materialwissenschaften und Werkstofftechnik , no. 33, p.575 – 580, (2002).

DOI: 10.1002/1521-4052(200210)33:10<575::aid-mawe575>3.0.co;2-1

[10] H. Salmang; H. Scholze, R. Telle: Keramik, Springer-Verlag Berlin Heidelberg, (2007).

[11] F. Klocke; W. König: Fertigungsverfahren 2 – Schleifen, Hohnen, Läppen, 4., neu überarbeitete Auflage, Springer-Verlag Berlin Heidelberg, (2005).