Facilities and Programfor Coating 8” Plates

Jeffrey Elam, Anil Mane, Qing Peng, Joseph LiberaArgonne National Laboratory

LAPD Collaboration MeetingJune 10, 2010

Argonne Flow-Tube ALD Coating Systems

2

2”

36”

33 mmdisc

siliconwitness

siliconwitness

• ~1% thickness increased at the “Si block” location• Thickness increased as high as 30% after MCP locations

Thickness across the reactor Chemistry #1

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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

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12”

18”

ALD Indium-Tin Oxide in Large Substrate Reactor

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-50+5

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ativ

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Axial Distance (Inches)

Distance fromCenter (in)

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-6 -4 -2 0 2 4 6R

elat

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Distance From Center (Inches)

Very poor uniformity over large areas (± 45%) In2O3-catalyzed decomposition of O3

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Cyclopentadienyl Indium /Ozone (O3) → In2O3

Improved ALD ITO Process

Standard Deviation=3.1%

No ozone Excellent uniformity over large areas Process matters a lot

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Large substrate testing: ALD Chemistry #2

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Not optimized (same conditions as in flow tube)

Beneq TFS500

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Arrived: 5/18/10 Commissioning : 6/28/10

500 m

m

Large Area Reaction Chamber for Beneq

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10 trays

Tray top Tray Bottom

11.25”

17.5”

Two 8”x8” Tiles in Beneq Tray

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2 Tiles/Tray x 10 Trays = 20 Tiles per batch

Tray top Tray Bottom

8”x8” tile

8”x8” tile

Challenge: ALD in High Aspect Ratios

Aspect ratio of capillary arrays does not limit the exposure times

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For LAPD tiles, aspect ratio L/D = 60

Diethyl zinc (DEZ)/H2O → ZnO

Challenge: ALD on High Surface Areas

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Surface Area (SA) ~ 4αγAB (Jason McPhate, 12/09)• α = open area ratio = 0.65• γ = aspect ratio L/d = 60• AB = area of plate top sans pores ,

• 33 mm disc = 8.4 cm2

• 8”x8” tile = 412 cm2

Surface Areas of Capillary Glass:

Empty large area reactor: 0.3 m2

1x 8”x8” tile: 6.4 m2

Empty Beneq: 5.8 m2

20x 8”x8” tile: 129 m2

Surface Areas: Empty ALD tube reactor: 600 cm2 1x 33 mm disc: 1310 cm2

Coating High Surface Areas: Silica Gel Powder 100 micron particles, 30 nm pores Surface area = 100 m2/g, L/D ~ 2000 Powder bed fixture for ~1 g support

Self-limiting growth on planar and porous surfaces

Exposures increased by x100

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Al 2

O3 G

row

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ate

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ycle

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TMA Exposure (Torr s)

Silica GelPlanar Surface

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Wei

ght

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TMA Exposure (Torr s)

Coating High Surface Areas: Silica Gel Powder trimethyl aluminum (TMA)/H2O → Al2O3

Layer-by-Layer Al2O3 ALD

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l 2O3

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Al2O3 ALD Cycles

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Al2O3 ALD Cycles

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?

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