Fig. 2: Schematic diagram and structure model diagrams of the Kelvin connection devices.
From: Low limit of detection of the AlGaN/GaN-based sensor by the Kelvin connection detection technique
a Diagram of the Kelvin connection device; high force (H. F) and high sense (H. S) are connected to the drain terminal, low force (L. F) and low sense (L. S) are connected to the source terminal. VDS voltage is applied between the H. F and L. F to form the current loop. The voltage between the H. S and L. S is measured as VDS−S. The diagram on the left is the schematic diagram and that on the right is the OM (Optical microscope (OM) top view of the real device. b Device A. The open gate area of device A is deposited by the Au layer. AuNPs (Au nanoparticles) are electroplated on the Au gate, and the anti-BNP is immobilized on the AuNPs to selectively detect BNP. c Device B. The open gate area of Device B is bare AlGaN. Magnetic beads immobilized with anti-BNP are absorbed on the AlGaN surface with a permanent magnet on the back side of the chip.
