1. SSL-UCB, ALD MCP Test Progress After cleaning ML201-B-1 6nm ALD After cleaning ML201-B-2 12nm ALD

2. Initial Imaging Results on Standard MCPs with 6nm ALD coating, single MCP, phosphor Shows definite enhancement of brightness in ALD area, due to GAIN increase! No degradation of image quality, except at the boundary zone for coating No ALD No ALD ALD ALD 1150v MCP, 2800v Screen, UV floodPhotonis ML201-B-1 MCP, 86MΩ 1050v MCP, 2900v Screen, UV floodPhotonis ML201-B-1 MCP, 86MΩ

3. Initial Photon Counting Results with 12nm ALD coating, single MCP, phosphor Shows definite suppression of brightness in ALD area, UV QE reduction! No degradation of image quality, except at the boundary zone for coating ALD No ALD 1100v MCP, 2700v Screen, UV floodPhotonis ML201-B-2 MCP, 90MΩ

4. Initial Photon Counting on Standard MCPs Stacked as a pair with 6nm/12nm ALD coating Using our photon counting imaging detector (25mm cross delay line) we stacked the ALD coated MCPs in a pair, 6nm on top, 12nm underneath, with the ALD layers rotated to give four combinations of MCP configurations. GAIN MAP IMAGE 0 nm/0 nm 0 nm/0 nm 6 nm/0 nm 6 nm/0 nm 0 nm/12 nm 0 nm/12 nm 6 nm/12 nm 6 nm/12 nm 2400v MCPs, UV flood, MCP pair, Photonis ML201-B-1 (6nm) top, ML201-B-2 bottom (12nm) 2400v MCPs, UV flood, MCP pair, Photonis ML201-B-1 (6nm) top, ML201-B-2 bottom (12nm) Legend:- ?? nm/ ?? nm Top MCP / bottom MCP

5. Initial Photon Counting Results on Standard MCPs IMAGING Normal uncoated MCP area, BUT - low UV response due to small events being electronically rejected! 0 nm/0 nm 12 nm coated MCP area under uncoated MCP, higher UV response due to higher gain - norejected events. 6nm coated MCP over uncoated MCP, - low UV response due to ALD coating suppressing nichrome photoemission! 6 nm/0 nm 0 nm/12 nm 6nm coated MCP over 12nm coated MCP, - low UV response due to ALD coating suppressing the nichrome photoemission! 6 nm/12 nm

6. Initial Photon Counting Results on Standard MCPs 0 nm/0 nm Image MAP Histograms 6 nm/0 nm 0 nm/12 nm 12 nm MCP under uncoated MCP is 3.5x higher UV QE than 6nm coated on top of 12nm MCP uncoated MCPs are 1.5x higher UV QE than 6nm coated MCP on top of uncoated MCP 6 nm/12 nm

7. Initial Photon Counting Results on Standard MCPs GAIN MAP Normal uncoated MCP area, Lowest gain! 0 nm/0 nm 6nm coated MCP over uncoated MCP, - moderate gain increase! 12 nm coated MCP area under uncoated MCP, - moderate gain increase. 6 nm/0 nm 0 nm/12 nm 6nm coated MCP over 12nm coated MCP, - big gain increase! 6 nm/12 nm Average gain is about 5 x 106

8. Initial Photon Counting Results on Standard MCPs GAIN MAP Histograms 0 nm/0 nm 6nm on top plus 12 nm under gives >4x gain enhancement 6nm on top gives x2 gain enhancement 6 nm/0 nm 0 nm/12 nm 6nm on top of 12nm gives x2 gain enhancement 6nm on top or 12 nm under Gives similar gain enhancement 6 nm/12 nm

9. Initial Photon Counting Results on Standard MCPs Stacked as a pair with 6nm/12nm ALD coating Summary • ALD Al2O3 coatings decrease the UV efficiency significantly • Need to put ALD under the electrode if we want UV QE • ALD Al2O3 coatings increase the MCP gain significantly • Both top and bottom MCP coatings are beneficial • ALD Al2O3 coatings don’t seem to affect the imaging quality • Still to do • Consequences for background rates? • Wider range of applied voltages/gains • More detailed imaging performance issues • Scrubbing and thermal ramifications