Anode current saturation of ALD-coated Planacon MCP-PMTs

E. V. Antamanova; I. G. Bearden; E. J. Garcia-Solis; A. V. Harton; V. A. Kaplin; T. L. Karavicheva; J. L. Klay; Yu. A. Melikyan; D. V. Serebryakov; M. Slupecki; W. H. Trzaska

doi:10.1088/1748-0221/13/09/t09001

arXiv · 1807.03804

Anode current saturation of ALD-coated Planacon MCP-PMTs

E. V. Antamanova·I. G. Bearden·E. J. Garcia-Solis·A. V. Harton·V. A. Kaplin·T. L. Karavicheva·J. L. Klay·Yu. A. Melikyan·D. V. Serebryakov·M. Slupecki·W. H. Trzaska

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Abstract

We have measured and compared the characteristics of ALD-coated Planacon MCP-PMTs (XP85112/A1-Q-L) with their non-ALD counterparts (XP85012/A1-Q). While the later show excellent performance, the ALD-coated sensors have surprisingly low current saturation levels (~two orders of magnitude lower than expected) and extremely high gain recovery time (more than 7 orders of magnitude higher than expected). We suspect that these problems might be caused by the unexpected side-effects of the ALD process. To make a definite conclusion, more samples need to be tested, preferably from different production runs. If our observation were confirmed, it would mean a serious technological setback for ALD-coated MCP-PMTs.

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E. V. Antamanova, I. G. Bearden, E. J. Garcia-Solis, A. V. Harton, V. A. Kaplin, T. L. Karavicheva, J. L. Klay, Yu. A. Melikyan, D. V. Serebryakov, M. Slupecki, W. H. Trzaska. 2018-07-10. Anode current saturation of ALD-coated Planacon MCP-PMTs. https://doi.org/10.1088/1748-0221/13/09/t09001

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