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Backside nanotexturing fabricated by electroless metal assisted wet chemical etching, protected with a deposited thin silicon layer, is a new approach to create high bending strength silicon samples. Bending strength for protected nanotextured samples followed by CMP process was enhanced by ∼3.4 folds as compared to polished silicon samples, which emphasize the possibility of industrial implementation. The morphology of silicon deposition layer upon nanotexture influences the stress behavior, which need an adequate fabrication technique for uniform deposition at wafer scale. The thin protection layer upon nanotexture prevents the unwanted particle trapping, which affects the electrical performances of the device. Moreover, this technology provides a rupture resistive solution for IC, MEMS and photovoltaic devices for industrial implementation.

In this work, we present a novel viscometer array based on dynamic response of droplets driven by dielectric force. Each sensing element contains a small testing droplet (3 µL) sandwiched by upper and lower electrodes. When applying a bias voltage between the electrodes, the droplet changes its shape due to the dielectric force, causing capacitance change between the upper and lower electrodes. The viscosity of the droplet was measured from the time constant of the step response. The results show the sensing range of viscometer array is 10 cSt to 200 cSt less than 1000 ms.

Silicon nanostructures are extensively being researched for many different applications for industries. Here we present two different types of nanostructures, silicon nanoplates and nanoholes fabricated by electroless metal assisted wet etching for enhancing the bending strength by ~3.7 fold and ~6 fold respectively as compared to polished silicon samples which emphasize the dependence of bending strength on nanostructure morphologies. Roughness at the nanostructure bottom cause stress concentration to increase which degrades the bending strength. Moreover, this technology can open a pathway of flexible silicon substrates for flexible and bendable electronics.

Glass nanostructures were fabricated by wet chemical etching instead of using the complicated nanolithography and expensive dry etching process. Super hydrophilic glass with contact angle of 1° was created using this nanostructure with 92% transparency. Self-assembled monolayer of Perfluorodecyl-trichlorosilane (FDTS) was used to further make the glass super hydrophobic with contact angle of 151° without affecting its transparency. Polysilicon layer of 300 nm was deposited on glass substrate first and nanostructures were fabricated in this layer by metal assisted wet chemical etching. Thermal oxidation converted the silicon nanostructure to silicon dioxide nanostructure. This technology is producible on mass scale and useful in preparation of anti-fogging and self-cleaning glass.

This paper presents a novel sensing array with tunable sensing ranges for dynamic tactile sensing. Each element in the array contains a droplet with variable shape. By controlling the dielectric force applying on the droplet, the shape of the droplet can be controlled. The sensing range was tuned due to the variation of the droplet shape. This sensing array can be not only used in static tactile sensing but also in dynamic tactile sensing. The experiment result shows the sensing range, from 0.6 N to 1.05 N, can be tuned in 100 ms.

This paper presents a novel tactile sensing array with adjustable sensing ranges. Each sensing element contains a low dielectric constant (er) droplet covered with high er liquid. We controlled the contact angle of the droplet by controlling the electric flux passing through the element. Then, the sensing ranges and sensitivity were also adjusted due to the variation of the droplet shape. The results show the sensor's sensing range is easily adjusted from 0.33N ~ 1.05N to 0.04N ~ 0.60N. And the sensitivity is also adjusted from 1.47pF/N to 2.90.pF/N.

This work presents silicon flapping wings design with higher bending strength and low reflectivity for MEMS aircraft. The design was bio-inspired by the cicada wings which are having numerous nanostructures upon it. The nanostructure on silicon increases the bending strength by ~6 times. The higher strength silicon samples can successfully demonstrate the 100 μm thick bendable silicon by nanostructure surface texturing used for flapping wings. Moreover, same nanostructures act as antireflective layer due to improved light trapping for solar cell. The reflectivity of the nanotextured surface reduces to ~2%.

In this paper, we propose a novel dielectric liquid-based tactile sensor with three axial sensing ability and high sensitivity. The sensor which consists of 3 capacitors uses Polydimethylsiloxane (PDMS) structure to encapsulate two liquids, i.e. a polyalcohol droplet (with higher dielectric constant) and oil (with lower dielectric constant, surrounding). The three axial force signals are detected by the capacitance change due to the mechanical deformations of the capacitors and the position change of the droplet. The proposed sensor's sensitivities in z-, x-and y-axes are 2.02 pF/N, 0.472 pF/N and 0.496 pF/N, respectively. The high sensitivity with promising spatial resolution would satisfy requirements of humanoid robotic applications.

This paper presents a novel capacitive tactile sensor with high sensitivity for humanoid robots. The main structure of the sensor is a cubic ‘box’ (3 × 3 × 2.5 mm3) made of Polydimethylsiloxane (PDMS). Two dielectric liquids, i.e. a polyalcohol droplet (with a higher dielectric constant) surrounded by oil (with a lower dielectric constant), were sealed in the box under iso-density condition. Electrodes were fabricated on the upper and lower inner surfaces of the box to form a capacitor. The two liquids, sandwiched by the electrodes, increased the capacitance of the capacitor. The sensitivity of the sensor increased due to the novel configuration. The proposed sensor was fabricated by microfabrication technology. This sensor's sensitivity is 61.77%/N, which is 3.3 times greater than that of typical sensors containing no liquid.

In this work, we proposed a hybrid PDMS-silicon electrostatic actuator with a large stroke under low driving voltages. The device features a staggered vertical comb-drive suspended by PDMS springs. Because of the flexibility of PDMS, an initial staggered displacement was naturally formed due to the self-weight of the device. Experimental results showed that the combination of polymeric springs and silicon structures enabled the large stroke of 3.73 µm at 3.5 kHz. The presented heterogeneous integration technology improves the performance and may bring new functionalities to micro-systems.