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Contact Resistivity of Laser Annealed SiGe for MEMS Structural Layers Deposited at 210°C


Lowering the silicon germanium (SiGe) deposition temperature from the current 450°C to below 250°C will enable processing Micro Electro-Mechanical Systems (MEMS) on flexible polymer instead of on rigid silicon substrates or glass carriers. A major disadvantage of such a low temperature deposition is that the films are amorphous, with high hydrogen content and yield poor electrical and mechanical properties. To ensure films suitable for MEMS applications, a post-deposition laser annealing (LA) treatment is used. It is essential that the contact resistance between the SiGe MEMS structural layer and any lower electrode is minimized. In this work we investigate what beneficial effect a LA treatment can have on the contact resistivity of an initially amorphous SiGe MEMS structural layer with a bottom TiN electrode. We report a minimum contact resistivity of 2.14×10-3 Ωcm2.

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El-Rifai, J., Witvrouw, A., Aziz, A.A. et al. Contact Resistivity of Laser Annealed SiGe for MEMS Structural Layers Deposited at 210°C. MRS Online Proceedings Library 1299, 205 (2011).

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