Deep silicon etching

F. Larmer, A. Schilp, K. Funk, M. Offenberg, Bosch deep silicon etching improving uniformity and etch rate for advanced MEMS applications, Proc. MEMS 99, Orlando, FL, USA, 211-216, Jan. 17-21, 1999. 

Figure 8-7. Example of deep silicon etching accomplished by plasma proeessing.

Geear M, Syms RRA, Wright S, Hohnes AS (2005) Monolithic MEMS quadrupole mass spectrometers by deep silicon etching. lEEE/ASME J Microelectromech Syst 14 1156-1166... 

Kiihamaki J, Franssila S (1999) Pattern shape effects and artefacts in deep silicon etching. J Vac Sci Technol A17 2280... 

There are many photoresists available commercially. These can be categorised into positive and negative tone resists. Various formulations of resists have differing properties (viscosity, ultimate achievable resolution, substrate adhesion etc.). Several classes of resist have thus been developed for different electronic applications. For example, high-resolution photolithography for patterning of submicron transistors requires a different resist to that needed for deep silicon etching of micro-electro-mechanical-systems (MEMS) stmctures. 

Colloidal nanolithography, deep silicon etching and nanomolding are the techniques used to achieve fibrillar polymer sfructures which mimic the gecko foot hairs these nanofibrils are densely packed, perpendicular and strongly adhesive to a synthetic surface, and due to these characteristics are promising materials for integration in flexible membranes and exploitation of new adhesives [169]. 

In the selection of etch mask for deep glass etching, thick SU-8 is a choice, but SU-8 cannot be used in a HF bath (48%) because SU-8 does not adhere well to Si02 [123]. However, with a polycrystalline amorphous Si seed layer SU-8 adheres very well. For instance, with a 1.5-pm-thick polished poly silicon, a 50-pm-thick SU-8 can be deposited as the etch mask, leading to a maximum etch depth of 320 pm. Usually photoresist (2 pm thick) is only useful for shallow etch, less than 50 pm [123]. 

Corman, T., Enoksson, P., Stemme, G., Deep wet etching of borosilicate glass using an anodically bonded silicon substrate as mask J. Micromech. Microeng. 1998, 8, 84-87. 

H. Jansen, M. de Boer, R. Lengten-bergh, M. Elwenspoek, The black silicon method a universal method for determining the parameter setting of a fluorine-based reactive ion etcher in deep silicon trench etching with profile control, Proc. Micromechanics Europe 1994, 60-64. 

Bosch process Deep reactive-ion etching (DRIE) Etching single crystalline materials Physical-chemical etching Potassium hydroxide (KOH) etching Silicon etching... 

Advanced silicon etching (ASE ) Bosch Vanderbilt University, Nashville, TN, USA process DRIE (Deep reactive ion etching) ... 

Anisotropic silicon etching Deep reactive-ion silicon etching Electrochemical etching ... 

Sun W, Kherani NP, Hirschman KD, Gadeken LL, Fauchet PM (2005) A three-dimensional porous silicon p-n diode for betavoltaics and photovoltaics. Adv Mater 17 1230-1233 Tao Y, Esashi M (2005) Macroporous silicon-based deep anisotropic etching. J Micromech Microeng 15 764-770... 

Larmer F, Urban A (2003) Challenges, developments and applications of deep silicon reactive ion etching. Microelectronic Eng... 

Deep Anisotropic Etching of Silicon Using Low Pressure High Density Plasma. Presentation of Complementary Techniques and their Applications in Microtechnology. [Online]. Available http //scholar.google.de/scholar q=Cyrille+Hibert+icp btnG= hl=de as sdt=0 (accessed 21-July 2012). 

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