设计制作了一种应用于微型聚合酶链式反应(PCR)芯片的微加热器。然后按照PCR循环温度的要求,利用该加热器进行了PCR温度实验。微加热器采用与MEMS工艺兼容的溅射方法在Si基上制作,微加热器材料为金属Pt。通过控制施加电压大小及时间,进行了变性温度、退火温度和延伸温度实验。结果表明:在25V和32V电压控制下的温升速度分别为0.68℃/s和1.23℃/s。在断电自然冷却下的降温速度均达到1℃/s。在一个PCR循环周期中每个反应仓的平均功耗为50mW,最大功耗80mW,整个10mm×10mm芯片的最大功耗为0.96W。完成第一次PCR温度循环需要220s,之后的每次循环仅需要175s。
A micro heater used for micro polymerase chain reaction (PCR) chip was designed and fabricated. The thermal experiments were performed with the obtained micro heater according to the PCR cycling temperature requirement. The micro heater was fabricated on silicon substrate using micro-electromechanical systems (MEMS) compatible sputtering technology. The micro heater structural material is Pt. The experiments on heating the chip to the temperature in different PCR stages, saying, the denaturation, annealing and extending were conducted by means of applying different control voltage. The experimental results show that the temperature of ramping rate is 0. 68 ℃/s and 1.23 ℃/s correspondingly under the control voltages 25 V and 32 V. Its cooling rate both are 1 ℃/s in atmosphere environment. The average power dissipation of each reaction chamber is 50 mW and the maximum power dissipation is 80 mW in one PCR cycle. For a PCR chip with size of 10 mm × 10 mm, the total maximum power is 0. 96 W. The first thermal PCR cycle is 220 s, and in the following cycles the time needed is only 175 s.