A normally closed electrostatic parylene microvalve for micro total analysis systems

This paper presents an electrostatically actuated, normally closed microvalve for parylene microfluidics. The proposed valve structure isolates the fluid from the electric field, and hence results in relatively low actuation potentials (<60 V) irrespective of the working fluid. Hereby, the microvalve solves electrolysis or electrode shielding problems observed in electrostatic actuation in micro total analysis systems. To investigate leakage properties, microvalves were tested under pressurized flow with de-ionized (DI) water. No detectable leakage ratio was observed up to 20 kPa inlet pressure, due to the unique semicircular valve seat design. It was shown that the valve seat could be reconfigured to enable sealing at various pressure levels for different applications.


A three-scale compressible microsphere model for hyperelastic materials
Dal, Hüsnü; MIEHE, Christian (Wiley, 2018-11-09)
This paper presents a seminumerical homogenization framework for porous hyperelastic materials that is open for any hyperelastic microresponse. The conventional analytical homogenization schemes do apply to a limited number of elementary hyperelastic constitutive models. Within this context, we propose a general numerical scheme based on the homogenization of a spherical cavity in an incompressible unit hyperelastic solid sphere, which is denoted as the mesoscopic representative volume element (mRVE). The a...
Beker, Levent; Zorlu, Ozge; Külah, Haluk (2013-01-24)
This paper presents a wafer level attachment method for handling various shaped structures for MEMS processes, using parylene as an interlayer material. In this method, a handle wafer containing pillars and perforations is utilized, and structures are attached to the handle wafer through a parylene coating process realized at room temperature with no applied force. It is observed that pillars with 20 mu m height, 2.5 mm side length, and 4.5 mm spacing can successfully be used to attach two 4 '' substrates t...
A low-cost rate-grade nickel microgyroscope
Alper, Said Emre; Silay, Kanber Mithat; Akın, Tayfun (Elsevier BV, 2006-11-08)
This paper presents a low-cost microgyroscope with a resolution in the rate-grade at atmospheric pressure, which is fabricated using a CMOScompatible nickel electrofonning process. Angular rate resolution of the gyroscope is increased by matching the resonance frequencies of the drive and sense modes close to each other using symmetric suspensions and electrostatic frequency tuning; whereas, undesired mechanical coupling between the two modes during matched mode operation is reduced by the fully decoupled g...
Çip-Üstü-Laboratuvar Uygulamaları için Elektrostatik Mikro Kapak Tasarımı
Yıldırım, Ender; Külah, Haluk (2010-04-21)
Bu bildiri, yüzey mikro işleme yöntemleriyle, çip-üstülaboratuvar (lab-on-a-chip) uygulamaları için üretilmiş yeni bir elektrostatik tahrikli mikro kapak tasarımını ve üretimini anlatmaktadır. Çip-üstü-laboratuvar uygulamaları genellikle düzlem içi mikro akışlar içermektedir. Burada anlatılan mikro kapak, düzlem içi akışa paralel bir diyaframın, elektrostatik kuvvetler yardımıyla akış yönüne dik olarak hareket ettirilmesi yöntemiyle çalışmaktadır. Bildiride, mikro kapağın çalışma prensipleri sunulmuş, kapağ...
An Industrially useful means for decomposing and differentiation of harmonics components of periodic waveforms
Dölen, Melik (Institute of Electrical and Electronics Engineers (IEEE); 2000-10-12)
This paper presents efficient methods to estimate the spectral content of (noisy) periodic waveforms that are common in industrial processes. The techniques presented, which are based on the recursive discrete Fourier transform, are especially useful in computing high-order derivatives of such waveforms. Unlike conventional differentiating techniques, the methods presented differentiate in the frequency domain and thus are quite immune to uncorrelated measurement noise. This paper also shows the theoretical...
Citation Formats
E. Yıldırım, M. F. Arıkan, and H. Külah, “A normally closed electrostatic parylene microvalve for micro total analysis systems,” SENSORS AND ACTUATORS A-PHYSICAL, pp. 81–86, 2012, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/46520.