Update on 8” MCP Coating in Beneq Jeffrey Elam December 20, 2011 Large Area Picosecond Photodetector Group Meeting Go to ”Insert (View) | Header and Footer" to add your organization, sponsor, meeting name here; then, click "Apply to All"
Coating 8” MCPs in Beneq 300 mm chamber
Flow Restrictors
First Coating with Flow Restrictors – no MCP JE1421: 12/16/2011, 500c 3-5-1-10 TMA/H2O, no MCP, flow restrictors installed 612 625 628 flow 632 631 630 629 627 625 629 625 G=1.25 ds%=0.78 mm%=3.19 614 With flow restrictors installed and 1 s H2O, works great! (still no MCP)
First Coating with Flow Restrictors and MCP
Summary of Coating Experiments
Summary of Coating Experiments No MCP – all look pretty flat. With MCP – all show hump. Hump gets worse with larger H2O exposures Hump is seen in both x and y. Appears at borders of MCP, shifted downstream in x-direction Hypothesis – our biggest problem is that the MCP is trapping H2O. This is released during TMA dose, diffuses out in all directions. Where TMA meets H2O we get a hump.
Extreme Example JE1417: 12/14/2011, 500 c 3-5-3-5 TMA/H2O, MCP suspened 12mm over plate 793 918 677 827 716 801 913 779 731 967 837 682 839 955 G=1.54 sd%=12.8 mm%=33.6 759