Pyroelectric electron emission from nanometer-thick films of PbZr_xTi_(1-x)O_3

摘要

We report pyroelectric emission from PbZr_xTi_(1-x)O_3 (PZT) thin films on nanometer-sharp tips. The epitaxial PZT films are 30 nm thick and grown directly on single-crystal silicon tips. Pyroelectric emission occurs for heating rates of ≥50℃/min in a 20V/μm external field. The emission current is a maximum of 240 nA when the heating rate is 100℃/min and the electric field strength is ≥6.7 V/μm. The emitted charge is ～7% of that expected for a perfect thin film emitter of epitaxial PbZr_xTi_(1-x)O_3. We calculate that pyroelectric emission can occur without an applied field if the heating rate exceeds 4.0 × 10~7 ℃/min.