Micro-biochemical reactor with integrated Pt heater/sensor: Fabrication and analysis

In this paper, two different types of micro-biochemical reactors, one on a silicon substrate and the other on a glass substrate, which are encapsulated by an upside down glass wafer that contains a cavity, are proposed. The reactors were fabricated by micro-blasting, wet etching, and polymer bonding. The main objective of this research was to develop a micro-biochemical reactor that could achieve rapid thermal cycling and real-time temperature measurements without calibration and that would consume less power. Steady-state temperature- distribution simulations for the two kinds of chambers, a glass-silicon bonded chip and glass-glass bonded chip, were carried out using finite element analyse (FEA). The temperature uniformity and gradient, regarding the effects of the Pt heater inside each chamber, were investigated. The results clearly demonstrated the effectiveness of glass in blocking the dissipation of heat to the substrate. The power consumption of the two kinds of chambers, glass-silicon bonded chip and glass-glass bonded chip, were measured and compared to that of a conventional chip. In particular, the power consumption of the glass-silicon bonded chip was reduced by 39 %, 33 %, and 31 % for annealing (55 °C), extension (72 °C), and denaturation (94 °C), respectively. These results show that the micro-biochemical reactor, realized by using a glass-glass bonded chip can perform real-time temperature sensing without calibration and rapid thermal cycling while using less power.