SU-8 Testing (v1g) Thin SU8 on glass slide Test: (1)Soft Bake (SB) and (2)Post Exposure Bake (PEB) 1

“Control” Recipe Spin Coating: rpm; rpm –expected thickness: 600 nm Soft Bake (SB): 60 93°C Exposure: W PEB: 93°C Develop: 4 min in SU8 developer SU8 developer rinse IPA rinse/Nitrogen Dry 2

1 st Set of Tests 4 samples; 8 devices/sample 4 Wells (W)+4 Blanks (B)/sample S1: “Control”: Misaligned (see next slide); All shorted; R(W) ~ 8.6 Ω; R(B) ~ 10 Ω Test Parameters for S2-4: –SB (RT Evap) and 60°C, same times for each S2: 8 min: R(W) = (2.7±0.8) Ω; R(B) = (11±0) MΩ; C(B) = (15.0 ± 0.1) pF S3: 13 min: Also misaligned (see next slide) R(W) = (4.9±?) Ω; R(B) = (6 ± 8) MΩ; C(B) = (17.0 ± 0.5) pF S4: 15 min: R(W) = (4 ± 1) Ω; R(B) = (11±0) MΩ; C(B) = (17 ± 0) pF Cracking patterns seen in S2, S3, S4 3

Findings/Discussion 1 st Set “Control”: All shorted –The “misalignment” ONLY causes 1.Top contacts don’t fully overlap guide circles on bottom that could result in the top contact not covering the well (is this the case? If not say so) – will NOT cause short 2.Top contacts touching two exposure regions –either single + double exposures (normal) – NOT cause short, –or single + no exposures (should not happen but may - according to Mark, but microscopy can tell us – presence of a well – check to confirm and revise here …) – MAY cause short (ONLY no exposure) RT Evap + 60°C at various times: All good –All Wells are shorted with a narrow range of R –All Blanks have good Cs also with narrow range Next thing to do is to estimate thickness from geometry from C –The two longer time ones exhibit ~10% larger C (difference in dielectric constants or thickness?) –All three show undesirable cracking patterns (under baked/sticky surface or over baked – low solvent, bubbling etc.?) 4

2 nd Set of Test Samples 4 samples 2 “Controls”: S5-6 Test Parameters for S7-8: –1 min 93°C and Vary SB 60°C S7: SB: 2.5 min S8: SB: 5 min 5

2 nd Test Results - “Control 1” S5 DeviceCapacitance( pF) Resistance( Ω) Type 129.4B 20.5W x10 6 B 424W 524B 67W 7 421B 817W Summary: W: 4/4 Shorted B: 3/4 Shorted R(W): (12 ± 10) Ω Excluding #3 R(B): (158± 230) Ω C(B,#3) – very low (9.38 pF) compared to 1 st set but comparable to S6 (also a Control - next slide). 6

“Control 2” S6 DeviceCapacitance( pF) Resistance( Ω) Type 1 Damaged9.74.6x10 6 W x10 6 B 3 Damaged x10 5 W x10 7 B 5142W x10 7 B 746W x10 4 B Summary: W: 2/4 Shorted (2 Damaged by high voltage – 1V) B: 0/4 Shorted R(W): (94± 68) Ω; C(B): (9.6± 0.5) pF 7

2.5 min SB S7 DeviceCapacitance( pF) Resistance( Ω) Type 113.4W 2428B 310.8W 4294B 53.7W 65.7B 74.1W 811.6B Summary: All Shorted R(B): (185 ± 211) Ω; R(W): (8 ± 5) Ω 8

5 min SB S8 DeviceCapacitance( pF) Resistance( Ω) Type 14.8W 216B 31.9W 444B 54.3W 6?B 7*15.16Very HighW x10 6 B Summary: W: 3/4 Shorted (why not 4/4?) B: 3/4 Shorted R(Blank): (30 ± 20) Ω (#8 excluded) R(Well): (3.7 ± 1.6) Ω (#7 excluded) 7*: Re-measured and consistent with capacitance 9

Findings/Discussion for 2 nd Set (S5-S8) The two “Controls”: –S5 is essentially all shorted, but R(B) > 10R(W) –S6 is nominally good aside from the 2 damaged devices. But, the 2 shorts are too resistive (~90 Ω) compared to the “benchmark” Set 1 (~few Ω). –C(B) are ~ 9.5 pF rather than pF for set 1 (thicker, lower dielectric constants, etc?) –The “Control” recipe is at best marginal thus unreliable (2 shorted and one nominally good out of 3 samples in sets 1 and 2) – consistent with prior Si wafer work (Matt) S7 and S8 are all shorted, but 20R(W) < R(B) and R(W)<10Ω, These are more consistent with Set 1 aside from being all shorted. The one good blank out of S8 has capacitance consistent with Set 1 capacitances (S2). 10

“Control 20x This image size is good (covering the entire crossbar) – perhaps larger ones covering up to the reference dots would be even better; at the current stage, there’s no need to have too many zoomed in images. 11

“Control 2” 100x 12

“Control1” 100x 13

2.5min SB 100x 14

5min SB 100x 15

3 rd Set of Test Samples 2 samples Test Parameters for S9-10: –1 min 93°C and Vary SB 60°C (longer SB compared to 2 nd set) S9: SB: 8 min S10: SB: 12 min 16

Back Contact not continuous – visually can’t see where it’s broken Measured Cs (can measure 2-terminal R) W: 2/4 Shorted B: 1/4 Shorted C(B): (19.3 ± 0.6) pF (excl. #2) DeviceCapacitance( pF) Resistance( Ω) Type 1W 2 B 312W 419B 5W 619B 7 W 820B 8 min - S9 17

12 min - S10 DeviceCapacitance( pF) Resistance( Ω) Type 14.5W 218B 36.7W 4121B 53.9W 6127B 75W 8 118B Summary: W: 4/4 Shorted B: 4/4 Shorted Avg Well Resistance: 5.0± 1.2Ω Avg Blank Resistance: 96± 52Ω Double Exposed (16s) 18

Discussion/Findings of Set 3 S9: –pretty much all open circuit –C(B) slightly higher than Set 1: 19 pF vs 15 and 17 pF –Current measurements unreliable because the back contact is not continuous without visual “flaws” S10: –All shorted –10R(W) < R(B) –Consistent with Set 2 19