A new technology for micromachining of silicon: dopant selective HF anodic etching for the realization of low-doped monocrystalline silicon structures

The sharp selectivity of HF anodic etching between p-Si and n-Si is used to realize monocrystalline silicon microstructures, in this case suspended beams, making use of masked implantation of phosphorous for the definition of the geometry. This technology offers opportunities in the field of micromachining of silicon for micromechanical applications. The technology is complementary to bulk micromachining (anisotropic KOH or EDP etching, or isotropic HF/HNO/sub 3/ etching) and surface micromachining with sacrificial-layer techniques.<
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