A piezoelectric micro-cantilever bio-sensor using the mass-micro-balancing technique with self-excitation

Abstract

A biosensor was developed for using in a LabOn-a-Chip (LOC). The sensor detects the change in the resonance frequency of a micro-cantilever with a piezoelectric film. This is the mass micro-balancing technique, which has been successfully used for detecting bio-materials in the quartz crystal microbalance (QCM). The PZT film, a piezoelectric film, is designed to act as both sensor and actuator. The geometry of the micro cantilever is optimized to maximize the sensitivity and minimize the environmental effects such as viscous damping and added mass effect in liquid. The fabricated sensor is composed of a 100 lm long, 30 lm wide, and 5 lm thick cantilever with a 2.5 lm thick piezoelectric (PZT) layer on it. The ratio of thickness to length of the micro cantilever is very high compared to others in micro cantilever-based studies. This high aspect ratio is the key to maximize the sensitivity and minimize the environmental effects. The fabricated micro sensor was tested by detecting the mussel gluing protein, the insulinanti insulin binding protein and the poly T-sequence DNA.

Design and Fabrication of a Novel T-Shaped Piezoelectric ZnO Cantilever Sensor

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“…To date, lead zirconate titanate (PZT) is one of the most widely exploited and extensively used piezoelectric materials. For example, Lee et al [2] developed a PZT microcantilever biosensor for using in a lab-on-chip (LOC). However, there are a few unsolvable problems for PZT thin films: (1) the crystallization temperature of PZT is in the range of 600-700 • C, which is not compatible with the CMOS integration [3] (2) a high electric field for poling is necessary, which may be difficult for PZT thin films that have some defects or pinholes [3] (3) the performance is gradually deteriorative due to aging effect [3] (4) PZT is highly toxic, and its toxicity is further enhanced due to its volatilization at high temperature particularly during calcination and sintering, causing environmental pollution [4].…”

Film bulk acoustic resonators (FBARs) as biosensors: A review

“…Biosensors are analytical devices which combine a biologically sensitive element with a physical transducer to selectively and quantitatively detect the trace of biomarkers such as DNA (Auer et al 2011;Lin et al 2010;Nirschl et al 2009), proteins (Kanno et al 2000;Nirschl et al 2009;Quan et al 2011;Quershi et al 2009;Sapsford and Ligler 2004;Zhao et al 2012a), and cells (Ayala et al 2009). There are different technologies that have been used for biosensors, such as electrochemical impedance spectrometry (EIS) (Ge et al 2014;Zhu et al 2014), surface plasmon resonance (SPR) (Cao et al 2006;Liedberg et al 1983), micro-cantilever (MCL) Lee et al 2007) and acoustic wave (Flewitt et al 2015;Guo et al 2015;Katardjiev and Yantchev 2012;Nirschl et al 2010;Voiculescu and Nordin 2012). The electrochemical biosensors typically have low sensitivity, while the other two types of technology-based biosensors have very high sensitivity, but are very expensive to manufacture and complex in operation.…”

Resonant efficiency improvement design of piezoelectric biosensor for bacteria gravimetric sensing

“…In recent years, many biosensors have been widely used in ultra-small mass detection [1][2][3], such as surface plasmon resonance (SPR), guided mode resonance (GMR) and piezoelectric biosensor. SPR and GMR are based on refraction change to calculate the loading mass.…”