Silicon nanowire field-effect transistor(SiNW-FET)sensors possess the ability of rapid response,real-time,and label-free detection with high sensitivity and selectivity in the analysis of charged molecules.Their nano-...Silicon nanowire field-effect transistor(SiNW-FET)sensors possess the ability of rapid response,real-time,and label-free detection with high sensitivity and selectivity in the analysis of charged molecules.Their nano-scale size makes them well suited for ultralow detection of charged molecules,but also brings the uniformity fabrication challenging,thus limiting their large-scale application.By a horizontal control approach,highly controllable silicon nanowires arrays at the top of the silicon-on-insulator(SOI)wafer(T-SiNW)were developed in our previous work.To further improve the device uniformity,here a novel SiNW fabricated approach was carefully designed by the combination of horizontal and vertical control.The new silicon nanowires appeared at the bottom of the top silicon layer(B-SiNW).The B-SiNW has a relatively low requirement on the fabrication process and better device uniformity compared to T-SiNW.These improvements resulted in the B-SiNW device with a lower current fluctuation(4.1 nA with 5.1%variations)in the flowing liquid,compared to the T-SiNW device(4.4 nA with 11%variations).Further,in quantitative detection of 40 ng/mL MMP-9,the B-SiNW sensors provided larger signals and lower fluctuation(normalized average response value:0.57 with 4.2%variations),compared to the T-SiNW sensors(0.41 with 12.1%variations),thus indicating a more accurate bio-analysis application of the B-SiNW sensor.This work advances the nanowire sensor technology a step closer toward large-scale application to create stable sensing platforms in disease diagnosis and monitoring.展开更多
基金the support from the National Key Research and Development Program of China(Nos.2018YFA0208500 and 2017YFA0207103).
文摘Silicon nanowire field-effect transistor(SiNW-FET)sensors possess the ability of rapid response,real-time,and label-free detection with high sensitivity and selectivity in the analysis of charged molecules.Their nano-scale size makes them well suited for ultralow detection of charged molecules,but also brings the uniformity fabrication challenging,thus limiting their large-scale application.By a horizontal control approach,highly controllable silicon nanowires arrays at the top of the silicon-on-insulator(SOI)wafer(T-SiNW)were developed in our previous work.To further improve the device uniformity,here a novel SiNW fabricated approach was carefully designed by the combination of horizontal and vertical control.The new silicon nanowires appeared at the bottom of the top silicon layer(B-SiNW).The B-SiNW has a relatively low requirement on the fabrication process and better device uniformity compared to T-SiNW.These improvements resulted in the B-SiNW device with a lower current fluctuation(4.1 nA with 5.1%variations)in the flowing liquid,compared to the T-SiNW device(4.4 nA with 11%variations).Further,in quantitative detection of 40 ng/mL MMP-9,the B-SiNW sensors provided larger signals and lower fluctuation(normalized average response value:0.57 with 4.2%variations),compared to the T-SiNW sensors(0.41 with 12.1%variations),thus indicating a more accurate bio-analysis application of the B-SiNW sensor.This work advances the nanowire sensor technology a step closer toward large-scale application to create stable sensing platforms in disease diagnosis and monitoring.
