用于介電泳操縱的C-MEMS電極設(shè)計與制備技術(shù)研究.pdf

1、華中科技大學碩士學位論文用于介電泳操縱的C-MEMS電極設(shè)計與制備技術(shù)研究姓名：龔杰申請學位級別：碩士專業(yè)：機械電子工程指導(dǎo)教師：湯自榮;史鐵林20090520華 中 科 技 大 學 碩 士 學 位 論 文 華 中 科 技 大 學 碩 士 學 位 論 文 Abstract Dielectrophoresis(DEP) method was widely used in separation, transportation, trappi

2、ng or sorting of micro/nano particles in the fluids, the key for realizing the dielectrophoretic manipulation was to design and fabricate micro-electrode array for producing the required distribution of the electric fiel

3、d. Up to present, the electrode for dielectrophoretic manipulation was almost planar inert metal electrode fabricated by conventional bulk micromachining, which had some shortcomings, including complex fabrication proces

4、s, high cost, not flexible design, low efficiency and throughput manipulation and so on. The paper presented novel C-MEMS electrode could be used for dielectrophoretic manipulation, optimum design of the structure of el

5、ectrode was carried out based-on the numerical simulation of electric field, the fabrication process of C-MEMS electrode was improved using micromechanical interlocking. The main research contents of this thesis includes

6、 three aspects: The basic principle of DEP was explained, the induced effective dipole moment of typical micro-particle was solved using equivalent dipole model, such as dielectric spherical, ellipsoidal particles and sh

7、ell model for biological particles. Then calculation expression of DEP force was established in AC(alternate current) electric field. The space distribution of electric field and its gradient was obtained by the finite e

8、lement method, which was produced by C-MEMS electrode, it further analyzed the influence of the structure of electrode on their distribution. According to curve fitting, we summarized the relationship between DEP force o

9、f particles and various parameters of square column quadrupole electrodes. The DEP force is proportional to the square of the voltage applied on the electrode, inversely the cublic of the width of electrode and the quart

10、ic of the space-width ratio. As the height of electrode increasing, the effective DEP force was extended. Micromechanical interlocking was introduced to previous C-MEMS process solving inadequate adhesion of substrate.

11、The paper theoretically discussed the mechanism of micromechanical interlocking improving adhesion, the structure achieving micromechanical interlocking was designed which was similar to “ink-pot”, adhesion improvements

12、was qualitatively estimated by immersion experiment in heated 40% potassium hydroxide (KOH) solution. The experimental results was consistent with theory, their both demonstrated the method could effectively improve adhe