Printed Thermoelectric, Piezoelectric and Pyroelectric Energy Harvesters

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Printed Thermoelectric, Piezoelectric and Pyroelectric Energy Harvesters Professor Robert Dorey, Chair of Nanomaterials Thursday, 09 April 2015 1

Introduction Harvesting using films Creating film harvesters Performances Based on: Integrated Powder-based Thick Films for Thermoelectric, Pyroelectric and Piezoelectric Energy Harvesting Devices Robert A. Dorey IEEE Sensors Journal, vol 14, no 7, pp 2177-2184, 2014 Thursday, 09 April 2015 2

Introduction Thursday, 09 April 2015 3

Introduction typical architecture Functional Conducting Structural Thursday, 09 April 2015 4

Processing Temperature Processing Temperature Co-processing Ceramics Ceramics Metals Metals Glass & Si Polymers Glass & Si Polymers Thursday, 09 April 2015 5

Powder based films Power Larger volumes thick films powder based manufacturing PZT film before sintering Thursday, 09 April 2015 6

Co-processing Temperature induced degradation: Interdiffusion Evaporation Degradation Solutions: Low temperature e.g. < 750 C for PZT/Si Diffusion barrier e.g. ZrO 2 R.A. Dorey, S.B. Stringfellow, R.W. Whatmore, Effect of sintering aid and repeated sol infiltrations on the dielectric and piezoelectric properties of a PZT composite thick film, J.Euro.Ceram.Soc., 22, 2921-2926, 2002. Thursday, 09 April 2015 7

Manufacturing techniques Thursday, 09 April 2015 8

Deposition screen printing Thursday, 09 April 2015 9

Deposition tape casting & spray coating 50 mm Tape casting Spray coating Thursday, 09 April 2015 10

Powder sol gel Sol infiltration & spinning PZT sol Dry Pyrolyse Sinter & Crystallise Spinning of composite slurry PZT powder Thursday, 09 April 2015 11

Future manufacturing techniques Thursday, 09 April 2015 12

Structuring direct writing PZT features created by ink jet printing Thursday, 09 April 2015 13

Structuring pad printing Silver NPs deposited by pad printing Thursday, 09 April 2015 14

Structuring micromoulding PZT features created by micro moulding D. Wang, S.A. Rocks, R.A. Dorey, Micromoulding of PZT film structures using electrohydrodynamic atomization mould filling, J.Euro.Ceram.Soc., 29, 1147 1155, 2009.. Thursday, 09 April 2015 15

Structuring micromoulding Thursday, 09 April 2015 16

Structuring micromoulding PZT Spreading region Thursday, 09 April 2015 17

Structuring additive vs subtractive DRIE Powder blast Wet etch Micromould Thursday, 09 April 2015 18

Powders, inks & processing temperatures Powder Powder Carrier Binder Thickness Temperature ( C) Synthesis (µm) Drying Burnout Sinter Screen Mech 76 wt% Bi-Te 22 wt% 2 wt% 80 60 (hours) 250/10 m - Toluene Polystyrene Screen In situ 75 wt% Bi-Te 20.3 wt% - - 120/15 m 200/5 m 400/30 m (N 2 ) 550 (N 2 ) Screen In situ 79.6% ZnSb 18% None 171 150/10 m 330 C/20 m 380/20 m (N 2 ) Screen Mech 36-64 vol% 64-36vol% n/a 100-120 - - 300 (Ar) Bi-Te epoxy resin Screen Calcination 80 wt% PZT 19.2 wt% 0.8 wt% 80-200 150-950 Screen Calcination PZT Terpineol Ethyl 20-40 120/30 m 550/1 h 900/60 m cellulose 700/30 m Screen Calcination PZT - - 30 120/10 m - 925/30 m Screen Calcination PZT Terpineol & PVB-PVAc 22 - - 800/10 m ethyl acetate Screen Calcination Complex Terpineol Ethyl 24-30 - - 1000-1250/2 h perovkites cellulose Tape Calcination PZT - PVB 30 vacuum 600/3 h 950-1150 PSG Calcination 98 wt% PZT 4 wt% sol None 4 450/3 m 700/10 m 700/15 m PSG Calcination 60 wt% PZT 40 wt% sol None 20 250/60 s 450/15 s 720/20 m EPD Calcination PZT Acetic acid None 25 - - 900 (low O 2 ) EPD Calcination 30 wt% Al 2 O 3 ethanol PVB/PVAc - - - - Thursday, 09 April 2015 19

Powders, inks & processing temperatures Powder Powder Carrier Binder Thickness Temperature ( C) Synthesis (µm) Drying Burnout Sinter Screen Mech 76 wt% Bi-Te 22 wt% 2 wt% 80 60 (hours) 250/10 m - Toluene Polystyrene Screen In situ 75 wt% Bi-Te 20.3 wt% - - 120/15 m 200/5 m 400/30 m (N 2 ) 550 (N 2 ) Screen In situ 79.6% ZnSb 18% None 171 150/10 m 330 C/20 m 380/20 m (N 2 ) Screen Mech 36-64 vol% 64-36vol% n/a 100-120 - - 300 (Ar) Bi-Te epoxy resin Screen Calcination 80 wt% PZT 19.2 wt% 0.8 wt% 80-200 150-950 Screen Calcination PZT Terpineol Ethyl 20-40 120/30 m 550/1 h 900/60 m cellulose 700/30 m Screen Calcination PZT - - 30 120/10 m - 925/30 m Screen Calcination PZT Terpineol & PVB-PVAc 22 - - 800/10 m ethyl acetate Screen Calcination Complex Terpineol Ethyl 24-30 - - 1000-1250/2 h perovkites cellulose Tape Calcination PZT - PVB 30 vacuum 600/3 h 950-1150 PSG Calcination 98 wt% PZT 4 wt% sol None 4 450/3 m 700/10 m 700/15 m PSG Calcination 60 wt% PZT 40 wt% sol None 20 250/60 s 450/15 s 720/20 m EPD Calcination PZT Acetic acid None 25 - - 900 (low O 2 ) EPD Calcination 30 wt% Al 2 O 3 ethanol PVB/PVAc - - - - Thursday, 09 April 2015 20

Powders, inks & processing temperatures Powder Powder Carrier Binder Thickness Temperature ( C) Synthesis (µm) Drying Burnout Sinter Screen Mech 76 wt% Bi-Te 22 wt% 2 wt% 80 60 (hours) 250/10 m - Toluene Polystyrene Screen In situ 75 wt% Bi-Te 20.3 wt% - - 120/15 m 200/5 m 400/30 m (N 2 ) 550 (N 2 ) Screen In situ 79.6% ZnSb 18% None 171 150/10 m 330 C/20 m 380/20 m (N 2 ) Screen Mech 36-64 vol% 64-36vol% n/a 100-120 - - 300 (Ar) Bi-Te epoxy resin Screen Calcination 80 wt% PZT 19.2 wt% 0.8 wt% 80-200 150-950 Screen Calcination PZT Terpineol Ethyl 20-40 120/30 m 550/1 h 900/60 m cellulose 700/30 m Screen Calcination PZT - - 30 120/10 m - 925/30 m Screen Calcination PZT Terpineol & PVB-PVAc 22 - - 800/10 m ethyl acetate Screen Calcination Complex Terpineol Ethyl 24-30 - - 1000-1250/2 h perovkites cellulose Tape Calcination PZT - PVB 30 vacuum 600/3 h 950-1150 PSG Calcination 98 wt% PZT 4 wt% sol None 4 450/3 m 700/10 m 700/15 m PSG Calcination 60 wt% PZT 40 wt% sol None 20 250/60 s 450/15 s 720/20 m EPD Calcination PZT Acetic acid None 25 - - 900 (low O 2 ) EPD Calcination 30 wt% Al 2 O 3 ethanol PVB/PVAc - - - - Thursday, 09 April 2015 21

Powders, inks & processing temperatures Powder Powder Carrier Binder Thickness Temperature ( C) Synthesis (µm) Drying Burnout Sinter Screen Mech 76 wt% Bi-Te 22 wt% 2 wt% 80 60 (hours) 250/10 m - Toluene Polystyrene Screen In situ 75 wt% Bi-Te 20.3 wt% - - 120/15 m 200/5 m 400/30 m (N 2 ) 550 (N 2 ) Screen In situ 79.6% ZnSb 18% None 171 150/10 m 330 C/20 m 380/20 m (N 2 ) Screen Mech 36-64 vol% 64-36vol% n/a 100-120 - - 300 (Ar) Bi-Te epoxy resin Screen Calcination 80 wt% PZT 19.2 wt% 0.8 wt% 80-200 150-950 Screen Calcination PZT Terpineol Ethyl 20-40 120/30 m 550/1 h 900/60 m cellulose 700/30 m Screen Calcination PZT - - 30 120/10 m - 925/30 m Screen Calcination PZT Terpineol & PVB-PVAc 22 - - 800/10 m ethyl acetate Screen Calcination Complex Terpineol Ethyl 24-30 - - 1000-1250/2 h perovkites cellulose Tape Calcination PZT - PVB 30 vacuum 600/3 h 950-1150 PSG Calcination 98 wt% PZT 4 wt% sol None 4 450/3 m 700/10 m 700/15 m PSG Calcination 60 wt% PZT 40 wt% sol None 20 250/60 s 450/15 s 720/20 m EPD Calcination PZT Acetic acid None 25 - - 900 (low O 2 ) EPD Calcination 30 wt% Al 2 O 3 ethanol PVB/PVAc - - - - Thursday, 09 April 2015 22

Powders, inks & processing temperatures Powder Powder Carrier Binder Thickness Temperature ( C) Synthesis (µm) Drying Burnout Sinter Screen Mech 76 wt% Bi-Te 22 wt% 2 wt% 80 60 (hours) 250/10 m - Toluene Polystyrene Screen In situ 75 wt% Bi-Te 20.3 wt% - - 120/15 m 200/5 m 400/30 m (N 2 ) 550 (N 2 ) Screen In situ 79.6% ZnSb 18% None 171 150/10 m 330 C/20 m 380/20 m (N 2 ) Screen Mech 36-64 vol% 64-36vol% n/a 100-120 - - 300 (Ar) Bi-Te epoxy resin Screen Calcination 80 wt% PZT 19.2 wt% 0.8 wt% 80-200 150-950 Screen Calcination PZT Terpineol Ethyl 20-40 120/30 m 550/1 h 900/60 m cellulose 700/30 m Screen Calcination PZT - - 30 120/10 m - 925/30 m Screen Calcination PZT Terpineol & PVB-PVAc 22 - - 800/10 m ethyl acetate Screen Calcination Complex Terpineol Ethyl 24-30 - - 1000-1250/2 h perovkites cellulose Tape Calcination PZT - PVB 30 vacuum 600/3 h 950-1150 PSG Calcination 98 wt% PZT 4 wt% sol None 4 450/3 m 700/10 m 700/15 m PSG Calcination 60 wt% PZT 40 wt% sol None 20 250/60 s 450/15 s 720/20 m EPD Calcination PZT Acetic acid None 25 - - 900 (low O 2 ) EPD Calcination 30 wt% Al 2 O 3 ethanol PVB/PVAc - - - - Thursday, 09 April 2015 23

Powders, inks & processing temperatures Powder Powder Carrier Binder Thickness Temperature ( C) Synthesis (µm) Drying Burnout Sinter Screen Mech 76 wt% Bi-Te 22 wt% 2 wt% 80 60 (hours) 250/10 m - Toluene Polystyrene Screen In situ 75 wt% Bi-Te 20.3 wt% - - 120/15 m 200/5 m 400/30 m (N 2 ) 550 (N 2 ) Screen In situ 79.6% ZnSb 18% None 171 150/10 m 330 C/20 m 380/20 m (N 2 ) Screen Mech 36-64 vol% 64-36vol% n/a 100-120 - - 300 (Ar) Bi-Te epoxy resin Screen Calcination 80 wt% PZT 19.2 wt% 0.8 wt% 80-200 150-950 Screen Calcination PZT Terpineol Ethyl 20-40 120/30 m 550/1 h 900/60 m cellulose 700/30 m Screen Calcination PZT - - 30 120/10 m - 925/30 m Screen Calcination PZT Terpineol & PVB-PVAc 22 - - 800/10 m ethyl acetate Screen Calcination Complex Terpineol Ethyl 24-30 - - 1000-1250/2 h perovkites cellulose Tape Calcination PZT - PVB 30 vacuum 600/3 h 950-1150 PSG Calcination 98 wt% PZT 4 wt% sol None 4 450/3 m 700/10 m 700/15 m PSG Calcination 60 wt% PZT 40 wt% sol None 20 250/60 s 450/15 s 720/20 m EPD Calcination PZT Acetic acid None 25 - - 900 (low O 2 ) EPD Calcination 30 wt% Al 2 O 3 ethanol PVB/PVAc - - - - Thursday, 09 April 2015 24

Piezoelectric energy harvesters PZT micro energy harvesting cantilever Thursday, 09 April 2015 25

Performance Thursday, 09 April 2015 26

Printed piezoelectrics & pyroelectrics Architecture Process Active material thickness (µm) Substrate thickness (µm) Dimensions L x W (mm) Power (µw) Power density (µw/cm 3 ) Operational frequency (Hz) Bimorph Screen 20 (x2) n/a 6.5 x 5.5 33.2 @ 1 g - 344 Bimorph Screen 55 none 18 x 9-25-33@0.5 g 227 Unimorph Screen 65 (x2) 250 20 x 8 400-230 Unimorph Screen 22 12.3 (0.38-0.58) x - - 68-154 x 10 3 0.4 Unimoph PSG/spin 4 50 5 x 17 15.4 @ 1 g 97.9 @ 1 g 89 Unimorph Aerosol 15 20 8 x 6 200 @ 1.5 g 137.5 @ 1.5 g 112 Unimorph Tape cast 230 250 60 x 30-2083 8.2 Pyroelectric Screen 60-100 500 - - - ~ 10-3 Thursday, 09 April 2015 27

Printed piezoelectrics & pyroelectrics Architecture Process Active material thickness (µm) Substrate thickness (µm) Dimensions L x W (mm) Power (µw) Power density (µw/cm 3 ) Operational frequency (Hz) Bimorph Screen 20 (x2) n/a 6.5 x 5.5 33.2 @ 1 g - 344 Bimorph Screen 55 none 18 x 9-25-33@0.5 g 227 Unimorph Screen 65 (x2) 250 20 x 8 400-230 Unimorph Screen 22 12.3 (0.38-0.58) x - - 68-154 x 10 3 0.4 Unimoph PSG/spin 4 50 5 x 17 15.4 @ 1 g 97.9 @ 1 g 89 Unimorph Aerosol 15 20 8 x 6 200 @ 1.5 g 137.5 @ 1.5 g 112 Unimorph Tape cast 230 250 60 x 30-2083 8.2 Pyroelectric Screen 60-100 500 - - - ~ 10-3 Likely to be pw level Thursday, 09 April 2015 28

Printed thermoelectrics Architecture Processing Active material thickness (µm) In-plane (n) (Bi,Sb) 2 Te) 3 (p) Bi 2 (Se,Te) 3 In-plane Elements Seebeck coef. (µv/k) ZT Power factor (α 2 σ) mw/m 2 K Screen 80 5 123-0.06 - Power density (µw/cm 3 ) (unimat) Bi 2 Te 3 (20 K ΔT) Dispenser 120 62 200 @ RT 0.31 0.27 130 Film only Screen 80-140 0.61 (@RT) 2.1 - Bi 2 Te 3 Film only Ca 3 Co 4 O 9 Aerosol 55-150-170 (@300-700 C) - - - Film only ZnSb Screen - - 355-365 (@ 330-480K) Bi 0.85 Sb 0.15 /epoxy Screen 97 Ag-Ni Screen 22-25 @RT 0.6-1.1 @ ~RT 30 Multilayer (n) LaSrTiO 3 (p) Ni-Mo In-plane (n) Bi 2 Te 3 (p) Sb 2 Te 3 Π Cu/Ni Multilayer (n) 100 (p) 25 Coevaporation Electroplate 50 (n) 20 @ RT (p) 153 @ RT - 8 (n) 248 (p) 188 (n) 0.32 @623K (p) 0.04 @623K (n) 0.93 @ 300K (p) 0.26 @ 300K (n) 4.87 @ 300K (p) 2.81 @ 300K (200 K ΔT) 450 (360 K ΔT) 150 51 20.6 - - 0.012 (0.12 K ΔT) - Thursday, 09 April 2015 29

Summary Film based harvesters can be fabricated Thick films are reliant on consolidation of powders i.e. heat required Film forming techniques are continually improving Cheaper & quicker to fabricate than bulk systems Based on: Integrated Powder-based Thick Films for Thermoelectric, Pyroelectric and Piezoelectric Energy Harvesting Devices Robert A. Dorey IEEE Sensors Journal, vol 14, no 7, pp 2177-2184, 2014 Thursday, 09 April 2015 30

Contact details Professor Robert Dorey Chair in Nanomaterials Department of Mechanical Engineering Sciences, Faculty of Engineering and Physical Sciences, University of Surrey Guildford Surrey UK GU2 7XH r.dorey@surrey.ac.uk www.twitter.com/robert_dorey www.surrey.ac.uk Ceramic Thick Films for MEMS and Microdevices ISBN: 978-1-4377-7817-5 Thursday, 09 April 2015 31

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