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This paper presents the results of an experimental evaluation of a new type of piezoelectric ceramic device designed for use as a laser mirror tuner. Thin plates made from various materials were assembled into a circular bimorph configuration and tested for linearity of movement, maximum travel, and resonant frequency for varying conditions of clamping torque and mirror loading values. Most of the devices tested could accept mirror diameters up to approximately 1.3 cm and maintain a resonant frequency above 2 KHz. Typical mirror translation without measurable tilt was +/-20 microm or greater for applied voltages of less than +/-300 V.

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Semiconductor W A D has recently been gaining attention as a tool for the design of rad hard integrated circuits. Milanowski et al. [l] recently demonstrated how TCAD simulations could be used to predict edge-enhanced buried oxide hole trapping and its impact OR back channel leakage in SO1 MOSFETs. The accuracy of TCAD depends strongly on the accuracy of the underlying models of the density and distribution of hole trap precursors. The recent thermodynamics based "E' model" has shown succcss in predicting charge trapping density in a wide variety of simply processed oxides [2,3], but it has not yet been calibrated in two dimensions (2D). Currently, there'is no way to calibrate charge-trapping models in 2D or even reliably detect trapped oxide charge in 2D. Traditional trap114;d charge spatial profiling methods such as CV etchback experiments are only good for one dimension of infonnation. One family of techniques that is able to provide 2D imaging are the various scanning probe microscopies including scanning capacitance microscopy (SCM) [4], electrostatic force microscopy (EFM) [5], and scanning Kelvin probe force microscopy (SKPM) [6-81.In this abstract, we present two dimensional images of a cross sectioned SOI MOSFET using scanning Kelvin probe force microscopy (SKPM) and demonstrate the use of SKPM to produce 2D images of radiation induced trapped charge in SO2.Oxide hole injection was performed using UV photons filtered from a deuterium source in a vacuum (VUV, hclh 5 10.2 eV). Net oxide trapped charge density was calculated from shifts in high frequency capacitance vs. voltage measurements (CV) were performed at room temperature at 1 MHz with a HP 4284A and a mercury probe. Kelvin probe force measurements (see [6-81) were conducted using a Digital Instruments 3100 AFM in Interleave TM mode.Traditionally, CV measurements have been used to measure and profile charge trap density in Si02.Therefore, in order to aid in the interpretation of our SKPM measurements, we designed a simple test structure that could be used to directly compare the S U M 2-D results with CV results. Shown in Fig. 1, it consists of a 60nm thick oxide covered with pattemed photoresist and is divided into three regions. Region 1, the area for SKPM measurements, consists of a pattern of "crosses" with 7.5 um spacing. The area for mercury probe CV measurements consists of two regions, Region 2 is completely covered by photoresist and Region 3 is completely exposed. The regions of this structure allow us to: 1) selectively inject positive charge into the exposed regions of oxide (the photoresist absorbs the energetic UV photons used to inject charge), 2) accurately measure the fluence of the injected charge, 3) measure the density of charge trapped, and 4) make both SKPM and CV measurements on identically irradiated samples. Fig. 2 are (a) an AFM image and (b) an SKPM image of Region 1 following injection of approximately 7x10" holes / cm2 into the structure shown in Fig. 1. Immediately after hole injection, the photoresist was removed from...

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