Simulation and Typical Application of Multi-Step Diffusion Method for MEMS Device Layers

Abstract:

In MEMS device, heavily boron doped layers are widely used as structural layers. For the manufacture of the thick heavily boron doped layer (boron concentration ≥ 5×10¹⁹ cm^-3), conventional two-step method exposes disadvantages of low efficiency and high energy consumption. Hence, multi-step method is introduced to improve the energy efficiency. In our study, simulation of diffusion in silicon is carried out to compare multi-step method with conventional method. The simulation reveals that multi-step method obtains more quantity of boron dopants and shows better potential to fabricate thick heavily boron doped layers, compared to conventional method within the same total diffusion time. As a typical application of the multi-step method, a butterfly-shape resonant is fabricated.

• Periodical: Key Engineering Materials (Volumes 645-646)
• Pages: 341-346
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.645-646.341
• Online since: May 2015
• Authors: Ling Yun Wang*, Ru Hai Zhou, Yi Fang Liu, Cheng Zheng, Jian Fa Cai, Yong He
• Keywords: Boron Etch-Stop Technique, Heavily Boron Doped Layers, Multi-Step Diffusion Method

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