年7 月纳米技术与精密工程.pdf

6 4 Vol.6 No.4 2008 7 Jul. 2008 230027 (AFM) 50 (PZT) d31 - PZT d31 0 V10 V d31 48 pC/N 120 pC/N TN384 A 1672-6030200804-0249-05 Methods of Improving Charge Se Microprobe in Surface Data Reading WU Shao-yongXU Xiao-huiWU Ya-leiZHAO GangCHU Jia-ru Department of Precision Machinery and Precision InstrumentationUniversity of Science and Technology of ChinaHefei 230027China The piezoelectric charge sensitivity of nano-scaled data reading in atomic force microscopy(AFM) probe-array- based ultrahigh density data storage was studied. The sensitivity can be increased by two ways. Firstlythe sensitivity can be increased 50 by improving the design of passivation layer on the upper electrode. Secondlythe effective transverse piezo- electric coefficient of lead zirconate titanate(PZT) thin film d31 can be increased by introducing a direct current(DC) bias voltage in data readout circuitwhich will further the increase of the sensitivity. Based on direct piezoelectric effectsol-gel derived PZT thin films prepared on Si wafer cantilever have been used to validate the effect of DC bias voltage on d31. Effec- tive transverse piezoelectric coefficient d31 was enhanced from −48 pC/N to − 120 pC/N by increasing DC bias voltage from 0 V to 10 V. ultrahigh density storage piezoelectric thin film charge sensitivity effective transverse piezoelectric coef- ficient 2 2 [1] IBMLGStandford [2-5] 46.5 Gb/cm 300 Gb/in AFM