Indium tin oxide synthesized by a low cost route as SEGFET pH sensor

Abstract

Polycrystalline ITO films with good optoelectronics characteristics and homogeneous surface has been obtained upon annealing at 550 °C in N 2 atmosphere using a low-cost chemical vapor deposition (CVD) system. The films were evaluated as pH sensors in separative extended gate field-effect transistor (SEGFET) apparatus, exhibiting a sensitivity of 53 mV/pH, close to the expected Nernstian theoretical value for ion sensitive materials. The use of CVD process to synthesize ITO, as described here, may represent an alternative for fabrication of SEGFET pH sensors at low cost to be used in disposable biosensors since H + ions are the product of several oxireductase enzymes.

Facile Fabrication of P(Electrodeposition)/N(Solvothermal) 2D‐WS2‐Homojunction Based High Performance Photo Responsive, Strain Modulated Piezo‐Phototronic Diode

“…The diffraction peak were observed at 2θ=15.05°, 27.51°, 29.13°, 28.05°, 32.31°, 33.51°, 35.60°, 38.52°, 42.88°, 45.96°, 49.01°, 50.32°, 53.08°, 56.96°, 59.64°, 60.45°, 63.44°, 65.01°, 67.16°, 68.86°, 70.55°, 72.98°, 76.39°, 78.18°, 79.53°, 83.76°, 86.26° and 88.52° corresponding to the planes (002), (004), (004), (010), (010), (011), (012), (013), (006), (014), (015), (016), (110), (080), (008), (112), (017), (114), (020), (021), (018), (023), (116), (019), (025), (026), (0110) and (118), respectively. The 2θ=∼15.05° with (002) plane of WS 2 was ascribed to the formation of 2H phase WS 2 with respect to the JCPDS card #008‐0237 . Figure (b) shows the XRD pattern of p‐type WS 2 nanopebbles like structure where the diffraction peaks was observed at 2θ=13.55°, 26.55°, 42.44° corresponding to (002), (004), (006) family of planes, respectively.…”

“…The 2θ =~15.05°with (002) plane of WS 2 was ascribed to the formation of 2H phase WS 2 with respect to the JCPDS card #008-0237. [13,14] Figure 3(b) shows the XRD pattern of p-type WS 2 nanopebbles like structure where the diffraction peaks was observed at 2θ = 13.55°, 26.55°, 42.44°corresponding to (002), (004), (006) family of planes, respectively. The diffraction peak corresponding to the (002) family of plane at 2θ = 13.55°was attributed towards the formation of 3R phase WS 2 with respect to the JCPDS card #004-6164 .…”

EGFET Based Sensors for Bioanalytical Applications: A Review

“…For example, they are used in the monitoring of the quality of drinking water, soil analysis or in the inspection of processes in the food industry [76,77]. Different oxide substrates have been used as sensing membranes, among which tantalum oxide (Ta2O5), indium-tin oxide (ITO), tin oxide (SnO2), platinum dioxide (PtO2), vanadium anhydride (V2O5), xerogel, niobium oxide (Nb2O5), zinc oxide (ZnO), titanium dioxide (TiO2), and ruthenium oxide (RuO2), just to name a few [36,37,[78][79][80][81][82][83][84][85][86][87][88][89][90]. To further reduce the manufacturing costs, particularly those of the sensing membrane, recycled materials from other sectors have also been investigated.…”

High Performance EGFET-Based pH Sensor Utilizing Low-Cost Industrial-Grade Touch Panel Film as the Gate Structure

“…This separate scheme has many advantages to solve ISFET drawbacks, such as the flexibility of developing sensing element, simple to package, and suitable for disposable application. A variety of metal oxides have been developed as sensing film for EGFET-pH sensor including ZnO [13], [14], SnO 2 [15], Nb 2 O 5 [16], IrO X [17], TiO 2 [18], Ta 2 O 5 [19], PtO 2 [20] and ITO [21]- [26]. Meanwhile, many biosensors have been developed using EGFET structure, such as label-free DNA detection [27], glucose [28] and urea sensor [29], [30].…”