A facile method to improve tribological properties of silicon surface by combining nanogrooves patterning and thin film lubrication

Approaches and Challenges of Engineering Implantable Microelectromechanical Systems (MEMS) Drug Delivery Systems for in Vitro and in Vivo Applications

“…Surface micro/non-hierarchical structure designs and thin film lubrication are the two main methods used in BioMEMS to reduce adhesive and frictional problems. As demonstrated by Wang et al [76], silicon surfaces with micro grooves which were further modified by multiply-alklated cyclopentane thin films improved the tribological properties of the surface significantly.…”

Wetting behavior of textured silicon surfaces- an experimental study

“…Wetted regimes usually occurs on hydrophilic surfaces as they possess high surface energy, supporting high friction and adhesion. On the contrary, non-wetted regimes occur on hydrophobic surfaces as they possess low friction and low adhesion because of low surface energy [15].…”

“…There is enormous research been conducted by measuring static contact angle on artificial roughened surfaces referred to as micropatterns. 3D negative fingerprint and honeycomb textured surface were fabricated on SU8 coated silicon surface to produce a WCA of 81°and 95°respectively [16], Replicated epoxy micropillars of cylindrical type created by soft lithography provides a CA of 151° [17] , SU8 micropillars of square shape were fabricated on silicon by UV lithography achieves a WCA of 131° [18], Micro/nano grooves of varying pitch on silicon wafers by photolithography techniques produces a max contact angle of 48° [15], SU8 microdot patterns were fabricated by polymer jet printing on silicon samples by varying the distance between the dot (pitch) and found that SU8 textured surfaces have shown lower contact angle compared to spin-coated samples (SU8/Si) because of increased exposure of silicon surface [19]. Nanopatterns of PMMA with three different aspect ratios (holding time) were fabricated on silicon surfaces using simple capillary force lithography produced a contact angle of 99° [20].…”

Nanotribological properties of silicon surfaces nanopatterned by laser interference lithography

“…At a nanoscale, the real area of contact and the surface strongly affect friction in the contacts for samples with the same surface chemistry, according to the fundamental law of friction given by Bowden and Tabor that F f = τ A r , where τ is the shear strength, an interfacial property, and A r is the real area of contact. The real area of contact depends upon the patterned fractional silicon surface coverage [8]. The nanogroove fractional surface coverage R(%) is calculated as R(%) = NS space /S scan = NW /a, where N is the number of grooves, S space and S scan are the areas of the spacing and the patterned surface, respectively, W is the spacing width of the groove, and a is the length of the patterned surface perpendicular to the direction of the nanogrooves.…”

“…Traditionally, silicon is a widely used construction material for the fabrication of M/NEMS devices and, hence, most of the investigations are directed towards enhancing its tribological performance [1,4,5]. Many studies have shown that surface nanopatterning is an effective way to reduce adhesive and friction forces on micro/nano-scale, due to reduction of contact area [6][7][8][9][10]. Various methods, such as ion-beam roughening [11], focused-ion-beam milling (FIB) [12,13], template printing [6,10], current-induced local anodic oxidation [14], and others [15][16][17][18], are commonly used to fabricate micro/nano-structures.…”