A SiC p-i-n junction betavoltaic was fabricated, and electrical power output under irradiation from an 8.5GBq P33 source was monitored over a period of four half-lives of the radioisotope. The open-circuit voltage (VOC) of the device was 2.04±0.02V, and the peak power (Pout) was 0.58±0.02μW (2.1±0.2μW∕cm2) at 1.60V. The conversion efficiency (ηconv) was 4.5%±0.3% and the normalized power output indicates no device degradation over more than 3months (four half-lives of the source).

We have fabricated highly oriented, chemically prepared thin films of Pb(Zr,,aTio,m)03 (PZT 40/60) on both insulating and conducting substrates. While (100) MgO single crystals were used as the insulating substrates, the conducting substrates were fabricated by RF magnetron sputter deposition of 100-nm-thick (100) Pt films onto (100) MgO substrates. For comparison, we also fabricated PZT 40/60 films that had no significant preferential orientation on platinized MgO substrates. Sputter deposition of an underlying amorphous Pt film was used to fabricate randomly oriented PZT 40/60 films. Highly (001) oriented PZT 40/60 films had higher remanent polarization (61 pC/cm2 compared to 41 pC/cm2) and lower relative dielectric constant (368 compared to 466) than PZT 40160 films that were randomly oriented.

Compliant mechanisms are single-piece flexible structures that deliver the desired motion by undergoing elastic deformation as opposed to jointed rigid body motions of conventional mechanisms. Compliance in design leads to jointless, no-assembly ( Fig. 1), monolithic mechanical devices and is particularly suited for applications with small range of motions. The compliant windshield wiper shown in Fig. 1 illustrates this paradigm of noassembly. Conventional flexural mechanisms employ flexural joints that connect relatively rigid links as depicted in Fig. 2. Reduced fatigue life, high stress concentration and difficulty in fabrication are some of the drawbacks of flexural joints. Our focus is on designing compliant mechanisms with distributed compliance which employs flexural links (see Fig. 3) and have no joints (neither pin nor flexural joints) for improved reliability, performance, and ease of manufacture. Distributed compliant mechanisms derive their flexibility due to topology and shape of the material continuum rather than concentrated flexion at few regions. This paper focuses on the unique methodology employed to design jointless mechanisms with distributed compliance. The paper also illustrates a compliant stroke amplification mechanism that was recently designed, fabricated and tested for MEMS application.

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