Chemical etching of Y-rotated quartz plates: experiments and theoretical approach

• Published in: Sensors and actuators. A. Physical. 1997-06, Vol.61 (1), p.405-414
• Main Authors: Leblois, T., Tellier, C.R., Messaoudi, T.
• Format: Article
• Language: English
• Subjects: Chemical etching; Y-rotated quartz plates
• ISSN: 0924-4247; 1873-3069
• DOI: 10.1016/S0924-4247(97)80297-X

A study has been made on the effect of the orientation of quartz plates on etching shapes resulting from a prolonged etching in an isothermal concentrated solution of ammonium bifluoride. Surface texture, as well as lateral underetching and concave corner undercutting characterizing the anisotropy of micromachining have been studied. The cuts investigated here are doubly rotated cuts with various angles of cut, such as φ 0 = 90° and θ 0 varies. Emphasis has been placed on surface features such as textures and flatness of surfaces studied by means of scanning electron microscopy and atomic force microscopy. These features are partly used to estimate the dissolution constants involved in the general equation of the dissolution slowness surface. The analysis of lateral underetching and corner undercutting gives important information in order to realize mechanical devices such as resonators with high performance on non-conventional cuts. In addition, numerical simulations of 2D and 3D etching shapes are given. A systematic comparison of theoretical predictions whith experiments allows us to discuss the suitability of the dissolution slowness surface.