Study On The Fabrication Of Bio-microarray Using GHz Bulk Acoustic Wave Resonators

Bio-microarray technology have been widely used in life science and medical test due to its distinct advantages,including high-throughput,multiplexing,minimal sample consumption and improved sensitivity.Therefore,approaches used to fabricate biomolecule microarrays with good quality and high efficiency have been attracting great attentions.At present,the main bio-microarray fabrication technologies include pin printing,microstamping,electro-inkjet printing and photolithography,etc.Though some of these methods have been successfully commercialized,they still suffer some drawbacks.For example,pins are easy to be consumed or damaged,nozzles are easy to be clogged,high cost,low biocompatibility,etc.Microarray fabrication needs to meet four key points:(1)the spots of microarray have good uniformity and morphology;(2)the spots of microarray have good size consistency;(3)the bioactivity of materials is well maintained;(4)low cost,simple fabricating process and easy to use.This paper proposed a new microarray fabrication method based on a GHz bulk acoustic wave resonator.We designed and fabricated a solidly mounted film bulk acoustic wave resonator(SMR)with a resonating frequency of 2.45 GHz via microelectromechanical technology.By applying a certain power to SMR to drive liquid via the excited acoustofluidic effect,the liquid surface will deform into a micron-scale liquid needle.Then microarrays can be fabricated by controlling the contact of the liquid needle and a substrate surface as well as the plane motion of the substrate via a precise XYZ stage.Compared with conventional microarray fabrication methods,the method we proposed here doesn't need any pins or nozzles,thus avoiding the problems caused by the use of pins or nozzles.With respect to the microarray quality,the microarrays fabricated by this method have very good uniformity and morphology as well as low coefficient of variation.Besides,the size of microarray spots can be well adjusted,and the minimum diameter of which is as low as 8?m(corresponding to droplet volume of femtoliter).The acoustic resonator based microarray fabrication method proposed in this paper has the advantages of low cost,easy to use and good bio-compatibility.In addition,since the SMR fabrication process in this paper is compatible with CMOS process,the SMRs can be easily integrated,thus achieving more rapid and efficient high-throughput fabrication of microarrays.