High sensitive detection of biomolecules with integrated THz sensor chip

We have developed a high sensitive biological sensor chip using a transmission line type terahertz device. The device was based on a transferred low temperature-grown GaAs layer that was bonded onto silicon substrates. Photoconductive switch elements for generating and detecting THz signals are fabricated on the LT-GaAs layer. The sensor chip has a round reservoir on a 1 mm long microstrip transmission line and is able to regulate the interaction length between samples and the THz wave. It can detect the difference between hybridized and denatured DNA molecule with minute volume less than 60 nl (8.4 fmol).