Polycrystalline Boron-doped Diamond Electrolyte-solution-gate Field-effect Transistor Applied to the Measurement of Water Percentage in Ethanol

An All-Solid-State pH Sensor Employing Fluorine-Terminated Polycrystalline Boron-Doped Diamond as a pH-Insensitive Solution-Gate Field-Effect Transistor

“…To decrease/improve the pH sensitivity of BDD SGFET sensor, the direct-wetted diamond surface, employed as the FET channel, was modified to partially fluorine-terminated BDD and partially oxygen-terminated BDD with the help of the method used in the previous study [ 8 , 9 , 10 , 11 , 16 ]. Figure 1 a,b illustrate the schematic diagrams of the pH-insensitive fluorine-terminated BDD (C-F BDD) SGFET surface and the pH-sensitive oxygen-terminated BDD (C-O BDD) SGFET surface.…”

“…We recently reported no-gate-insulator electrolyte-solution-gate field-effect transistors (SGFETs) with a single crystal diamond surface channel [4,5,6,7], with a polycrystalline diamond surface channel, and with a boron-doped diamond surface channel [8,9,10,11]. The ISFET has been a promising candidate for an integrated device to realize a high-response chemical sensor at a low cost.…”

“…After Bergveld [ 1 ] first presented an ion-sensitive field-effect transistor (ISFET), various types of ISFET have been presented, i.e., silicon-based ISFETs (Si-ISFETs) with an insulator of tantalum pentaoxide (Ta 2 O 5 ), with silicon nitride (Si 3 N 4 ), with aluminum oxide (Al 2 O 3 ) [ 2 ], and with a diamond-like carbon insulator [ 3 ]. We recently reported no-gate-insulator electrolyte-solution-gate field-effect transistors (SGFETs) with a single crystal diamond surface channel [ 4 , 5 , 6 , 7 ], with a polycrystalline diamond surface channel, and with a boron-doped diamond surface channel [ 8 , 9 , 10 , 11 ]. The ISFET has been a promising candidate for an integrated device to realize a high-response chemical sensor at a low cost.…”

Deoxyribonucleic-acid-sensitive Polycrystalline Diamond Solutiongate Field-effect Transistor with a Carboxyl-terminated Borondoped Channel

“…Polycrystalline diamond SGFETs were fabricated by a process described in our previous work. 14,16,[20][21][22] Following boron-doped polycrystalline diamond film deposition, two electrical contact pads of 200-nm gold on 30-nm titanium were deposited as a source/drain electrode using an electron beam evaporator (EB evaporation Model A500; Edwards). The electrical contact pads were positioned to give a 10-mm channel length and a 500-μm channel width.…”

“…To advance the commercial viability of diamond sensors, a polycrystalline diamond with an oxygen-terminated surface was also applied in our previous work. 14,[18][19][20][21] In this study, to verify the superiority and viability of an oxygen-terminated polycrystalline diamond surface with a boron-doped layer for biosensor, a partial carboxyl-termination was introduced for the polycrystalline diamond SGFET. A ss-DNA probe was immobilized on the polycrystalline diamond surface via amino coupling.…”