Colloidal lithography-based fabrication of suspended nanoporous silicon nitride membranes

Abstract

Nanoporous membranes provide a basis for constructing non-supported biomembranes, which enable biological processes such as ion and molecule transport through the biomembranes to be investigated under physiological conditions with ease of control. Preparation of such membranes usually requires expensive equipments and extensive experiences. In this paper, we provide a cheap and controllable scheme of high volume fabricating suspended nanoporous Si3N4 membranes on a Si wafer by combined colloidal lithography and standard Si fabrication technology including low cost ICP etching and anisotropic Si wet-etch. Si3N4 layers are grown on Si wafers. Polystyrene particles of 200-nm-diameter are then monodispersed on the Si3N4 layers based on electrostatic repulsions with an average density of 2%. This is followed by Cr masking, ICP etching and Si wet-etch processes to form suspended Si3N4 membranes with 200-nm-deep nanopores through the membranes. The well-aligned cylindrical nanopores have a low aspect radio of ca. 0.9, which would be beneficial to forming stable suspended lipid bilayers.National Basic Research Program of China [2007CB935603]; NSFC [20620130427]; MOST [2007DFC40440

Electrochemical Impedance Spectroscopy and Atomic Force Microscopic Studies of Electrical and Mechanical Properties of Nano-Black Lipid Membranes and Size Dependence

“…The nanoporous silicon nitride membranes were fabricated by colloidal lithography-based approach as has been reported previously . In brief, 4 in.…”

“…The nanoporous silicon nitride membranes were fabricated by colloidal lithography-based approach as has been reported previously. 27 In brief, 4 in. n-type Si (100) wafers of 320 μm thick were used with both sides grown successively with 300 nm thick silicon oxide (SiO 2 ) and 200 nm thick silicon nitride (Si 3 N 4 ) layers.…”

“…Herein, we present EIS and AFM studies of electrical and mechanical properties of nano-BLMs which are suspended on the nanopores of several different diameters embedded in the Si 3 N 4 membranes on a chip. The chips and nanopores are fabricated by colloidal lithography-based approach, 27 and therefore the aspect ratio of the nanopores is low and the cost of the chip is low as well. Within the framework of the present paper, the nanopores of 200, 400, and 700 nm in diameters are fabricated, based on which BLMs are constructed.…”

Nanohole arrays in chemical analysis: manufacturing methods and applications

“…[45][46][47][48][49][50] Suspended Si 3 N 4 nanohole arrays were fabricated on a Si wafer by depositing disordered nanoholes, followed by a selective etching of the silicon wafer. 51 Oxygen plasma controls the sphere size while at the surface providing a technique to tune the diameter of the nanohole. This is especially useful when low surface coverage is desired with small nanoholes, as the smaller spheres do not show the same adsorption behavior to surfaces.…”

Fabrication of functional silicon-based nanoporous membranes

“…Silicon pores have adjustable surface properties through chemical functionalization and are readily integrated into lab-on-a-chip devices. 9,11,[28][29][30] Porous silicon membranes have been created with a range of microfabrication techniques including focused ion beam (FIB) and e-beam lithography (EBL). For instance, Tong et al fabricated 25-nm-diameter cylindrical pores in 10-nmthick silicon nitride film by FIB.…”