Browsing by Subject "Piezoresistance"

Now showing 1 - 3 of 3

Open Access
Contact imaging in the atomic force microscope using a higher order flexural mode combined with a new sensor
(A I P Publishing LLC, 1996-01) Minne, S. C.; Manalis, S. R.; Atalar, Abdullah; Quate, C. F.
Using an atomic force microscope (AFM) with a silicon cantilever partially covered with a layer of zinc oxide (ZnO), we have imaged in the constant force mode by employing the ZnO as both a sensor and actuator. The cantilever deflection is determined by driving the ZnO at the second mechanical resonance while the tip is in contact with the sample. As the tip‐sample force varies, the mechanical boundary condition of the oscillating cantilever is altered, and the ZnO electrical admittance is changed. Constant force is obtained by offsetting the ZnO drive so that the admittance remains constant. We have also used the ZnO as an actuator and sensor for imaging in the intermittent contact mode. In both modes, images produced by using the ZnO as a sensor are compared to images acquired with a piezoresistive sensor.
Open Access
High‐speed atomic force microscopy using an integrated actuator and optical lever detection
(A I P Publishing LLC, 1996-09) Manalis, S. R.; Minne, S. C.; Atalar, Abdullah; Quate, C. F.
A new procedure for high‐speed imaging with the atomic force microscope that combines an integrated ZnO piezoelectric actuator with an optical lever sensor has yielded an imaging bandwidth of 33 kHz. This bandwidth is primarily limited by a mechanical resonance of 77 kHz when the cantilever is placed in contact with a surface. Images scanned with a tip velocity of 1 cm/s have been obtained in the constant force mode by using the optical lever to measure the cantilever stress. This is accomplished by subtracting an unwanted deflection produced by the actuator from the net deflection measured by the photodiode using a linear correction circuit. We have verified that the tip/sample force is constant by monitoring the cantilever stress with an implanted piezoresistor.
Open Access
Independent parallel lithography using the atomic force microscope
(A I P Publishing LLC, 1996-05) Minne, S. C.; Manalis, S. R.; Atalar, Abdullah; Quate, C. F.
Independent parallel features have been lithographically patterned with a 2×1 array of individually controlled cantilevers using an atomic force microscope. Control of the individual cantilevers was achieved with an integrated piezoelectric actuator in feedback with a piezoresistive sensor. Patterns were formed on 〈100〉 single crystal silicon by using a computer controlled tip voltage to locally enhance the oxidation of the silicon. Using the piezoresistor directly as a force sensor, parallel images can be simultaneously acquired in the constant force mode. A discussion of electrostatic forces due to applied tip voltages, hysteresis characteristics of the actuator, and the cantilever system is also presented.