Facilities and Program for Coating 8” Plates Jeffrey Elam, Anil Mane, Qing Peng, Joseph Libera Argonne National Laboratory LAPD Collaboration Meeting June 10, 2010

Argonne Flow-Tube ALD Coating Systems 2 2” 36” 33 mm disc silicon witness silicon witness

~1% thickness increased at the “Si block” location Thickness increased as high as 30% after MCP locations Thickness across the reactor Chemistry #1 3

4 Thickness across the reactor Chemistry #2 No thickness deviations near MCP Uniformity and ease of scaling in ALD are process-dependent

Large Substrate Reactor Integrates with existing ALD reactors Accommodates up to 12”x18” parts 5 12” 18”

ALD Indium-Tin Oxide in Large Substrate Reactor  Very poor uniformity over large areas (± 45%)  In 2 O 3 -catalyzed decomposition of O 3 6 Cyclopentadienyl Indium /Ozone (O 3 ) → In 2 O 3

Improved ALD ITO Process Standard Deviation=3.1%  No ozone  Excellent uniformity over large areas  Process matters a lot 7

Large substrate testing: ALD Chemistry #2 8 Not optimized (same conditions as in flow tube)

Beneq TFS500 9  Arrived: 5/18/10  Commissioning : 6/28/ mm

Large Area Reaction Chamber for Beneq trays Tray top Tray Bottom 11.25” 17.5”

Two 8”x8” Tiles in Beneq Tray 11  2 Tiles/Tray x 10 Trays = 20 Tiles per batch Tray topTray Bottom 8”x8” tile

Challenge: ALD in High Aspect Ratios  Aspect ratio of capillary arrays does not limit the exposure times 12 For LAPD tiles, aspect ratio L/D = 60 Diethyl zinc (DEZ)/H 2 O → ZnO

Challenge: ALD on High Surface Areas 13 Surface Area (SA) ~ 4αγA B (Jason McPhate, 12/09) α = open area ratio = 0.65 γ = aspect ratio L/d = 60 A B = area of plate top sans pores, 33 mm disc = 8.4 cm 2 8”x8” tile = 412 cm 2 Surface Areas of Capillary Glass:  Empty large area reactor: 0.3 m 2  1x 8”x8” tile: 6.4 m 2  Empty Beneq: 5.8 m 2  20x 8”x8” tile: 129 m 2 Surface Areas:  Empty ALD tube reactor: 600 cm2  1x 33 mm disc: 1310 cm 2

Coating High Surface Areas: Silica Gel Powder  100 micron particles, 30 nm pores  Surface area = 100 m 2 /g, L/D ~ 2000  Powder bed fixture for ~1 g support

Self-limiting growth on planar and porous surfaces Exposures increased by x100 Silica Gel Planar Surface Coating High Surface Areas: Silica Gel Powder trimethyl aluminum (TMA)/H 2 O → Al 2 O 3

Layer-by-Layer Al 2 O 3 ALD 16 Layer-by-layer growth on planar and porous surfaces Silica GelPlanar Surface

Outline of Research Plan  Single 8”x8” glass squares in large area reactor –Thickness uniformity with ellipsometry –Resistance uniformity with four-point probe –Composition with X-ray fluorescence (XRF) - destructive  Single 8”x8” capillary plate in large area reactor –Apply patterned electrodes (United Lens?) Measure resistance uniformity –composition (XRF), thickness (SEM) – destructive –MCP testing?  Multiple 8”x8” glass squares in Beneq –Thickness uniformity with ellipsometry –Resistance uniformity with four-point probe –Composition with X-ray fluorescence (XRF) - destructive  Multiple 8”x8” capillary plates in Beneq –Apply patterned electrodes Measure resistance uniformity –composition (XRF), thickness (SEM) – destructive –MCP testing? 17