Luận văn fabrication of in2o3 nanowires for self heated gas sensor application

Sung Chung Gwiy, Jac-Min Young graup’s micro heater [9] 9 Figure 1.7, Single SuO; NW conlacied with electron beam assisted platinum deposition ina four probes configuration before 2 and

IIANOI UNIVERSITY OF SCIENCE AND TECIINOLOGY

MASTER THESIS

Fabrication of InzO3 nanowires for self-

heated gas sensor application

NGUYEN THANII DUONG Duong.NT202353M(@sis.hust.edu.vn

Specialized: Materials science (Electronic materials)

Supervisor 1: Associate Professor Ph.D Nguyen Van Duy

Unit: International ‘Training Institute for Materials Science ([TIMS) Signature of supervisor

Supervisor 2: Ph.D.Phimg Thi Hong Vân

Unit: Hanoi University of Natural Resources & Environment Signature of supervisor

THANOI, 09/2022

DECLARATION

I hereby declare that this thesis represents my work which has been done after the registration for the degree of Master at the Intemational Training Institute of Materials Science — Ilanoi University of Science and Technology and has not been previously

included im a thesis or dissertation submilted to this or any other institution fora degree,

diploma or other qualifications

Hanoi, 224 Apnil, 2022 Nguyen Thanh Duong

ACKNOWLEDGEMENT

First of all, 1 am sincerely grateful to my thesis supervisor Assoc, Prof Nguyen Van Duy and Prof Nguyen Luc Lica - International ‘Iraining Institute of Materials Science, for allowing me this opportunity to be their student; all of their advices indication, and inspiration during the time T studied and canied ouL my Master thesis in ITIMS Tamm very proud fo have their whole guidaney, encouragement, and insight which

have always been invaluable

I would like to show my gratitude to all of teachers and staff not only in ITIMS but also in HUST to support me, I would like to send spectal thanks to Mr, Dang Ngoc Son and Mr Lai Van Duy - ITIMS tor sharing me the initial experiences and many usefil suggestions relevant to my work

Last but not the least, I would like to thank my family and my friends for their support

and encowagement

SUMMARY OF MASTER THESIS

In this work, we focused on the fabrication and testing of the H:S gas sensing

characteristic of the selt-heated Ins: nanowires sensor via a one-step CVD technique

and drop-casting on the IDE electrode The self-heated In-Q: NWs gas sensor was

measured at room temperature with different applied power toward H-S gas ‘This

performance was beller than the state-of-the-art tcroleater gas sensor The sensor is a potential canuidate for application related 10 H2S deleetion such as breath exhaled analysis aud cnvironmental monitoring

s for gas sensing application [1] 5

Figure 1.3 Sensing mechanism of metal oxide based gas scnsor [ ]

Figure 1.4, Power consumption and wrnperature characterized of Hwang WI's micro

tientcr [B| sec

Figure 1.5 Sung Chung Gwiy, Jac-Min Young graup’s micro heater [9] 9

Figure 1.7, Single SuO; NW conlacied with electron beam assisted platinum deposition ina four probes configuration before (2) and after (b) a few hours of operating in sclf-

Figure 2.5 Procadure of scli-heated InOs NWs based gas sensor 28 Figure 2.6, Gas sensitive measuring system at ITIMS (A), Diagram of the gas measuring

Figure 3.1 Menphotogy and snicrostructure of three eomposite simples at (A),(BY 0%: (C)CDY: 20 %, (ECE): 30 %; (G),CHD: 80 % mass ratio of Sn_ were observed by SEM

vũ

L Foundation of the {hesis ) cnmsesenmmonenenneititnieiannemnsnnne

1.3.1 InsOs mmafeTiali, smmosninineniminienmenmnesnnndd 1.3.2, InsOs nanowires I 2aS SEMSOT «sess sesssinnse sented

LA, Hazardous properties of H:$ 285 vaesscsesnomtnsnesintns nasntninssntntmnnnenned

CHAPTER 2 EXPERIMENTAL APPROACH

2.1 Synthesis of In:O nangwirvs is non re seo

LIST OF TABLES Table 1.1 Summary of publication reporting quantitative information about self-heated

‘Table 1.2 Publications reported self- heating effects in gas sensor using metal oxide

Table 3.1: Comparison with previous study at ITIMS with same approach method 44

Figure 3.14 Response to HS of the 80% w1 SnO2/i2O; NWs sensor used sel Heating

effect (Orange Tine) and seisor using the external heater at 200 °C (Blue linc) 44 Figure 3.15 Stability of sensor A External healer B Sel healed made 45 Figure 3.16 Selectivity of ImaO; NWS gas sensor toward NIIs, Ethanol and Il:S gas

Figuue 3.17 IsO› malcrisl H›§ ga sensing mechaniste -4?

L Foundation of the {hesis ) cnmsesenmmonenenneititnieiannemnsnnne

1.3.1 InsOs mmafeTiali, smmosninineniminienmenmnesnnndd 1.3.2, InsOs nanowires I 2aS SEMSOT «sess sesssinnse sented

LA, Hazardous properties of H:$ 285 vaesscsesnomtnsnesintns nasntninssntntmnnnenned

CHAPTER 2 EXPERIMENTAL APPROACH

2.1 Synthesis of In:O nangwirvs is non re seo

Figure 3.2 Distribution of TsO NWs onto silicon substrate with (A)10 ml (B)20 ml

Tigure 3.3 SEM nnage oŸTroO; nanowires dispersion em the eleelrode wi1h various ratio

Figure 3.4 (4D XRD pallern of 0%, 20%, 50 and 80% SnOwIn:03 NWs 34

Figure 3.5 EDX spect um of (A) Pưưe In:Os NW and (B),(C) SnO3/InzOy XW, 35

Tigure 3.6 The respdnse 0Í selÍ-heated TnsO; gas sensor versus time al different power

of 600, 800, 1200, 1200 pW (a) and the function of response with concentration H28

Figure 3.7 The response of sel heated 20% wi, SasiInOs NWs gas somisor versus lime

at different power af 300, 300 and 700 W (RT) (2) and the fimetion of response with concentration Hs§ gas ( Hi rrtereieireiririrrrerreoo.ÖB Figure 3.8 The response ot self-heated 50% wt 8nO›/InzQs NWS gas seIso versus time

at difterent power of 300, 500 and 700 wW (RT) (a) and the timetion of response with

concentration H-S gas (b) 39

Figure 3.9 The response ot self-heated 80% wt SnOv/br-Os NW gas sensor versus time

at difterent power of 300, 500 and 700 ,W (RT) (a) and the fimetion of response with

concentration H-S gas (b) - 40

Figure 3.10 Response and heating power graph of four fabricated sensors 4L

Figure 3.11 The response of self-heated 80% wt SnOyIn-O: NWWs gas sensor versus

time at different tempcrature of 200°C, 250 °C, 300 °C and 350 °C and the function of

Figtwe 3.12 Rssponse characferistic of [nsO; ~ nanowires gas sensor toward 5 ppm 11:5

Figure 3.2 Distribution of TsO NWs onto silicon substrate with (A)10 ml (B)20 ml

Tigure 3.3 SEM nnage oŸTroO; nanowires dispersion em the eleelrode wi1h various ratio

Figure 3.4 (4D XRD pallern of 0%, 20%, 50 and 80% SnOwIn:03 NWs 34

Figure 3.5 EDX spect um of (A) Pưưe In:Os NW and (B),(C) SnO3/InzOy XW, 35

Tigure 3.6 The respdnse 0Í selÍ-heated TnsO; gas sensor versus time al different power

of 600, 800, 1200, 1200 pW (a) and the function of response with concentration H28

Figure 3.7 The response of sel heated 20% wi, SasiInOs NWs gas somisor versus lime

at different power af 300, 300 and 700 W (RT) (2) and the fimetion of response with concentration Hs§ gas ( Hi rrtereieireiririrrrerreoo.ÖB Figure 3.8 The response ot self-heated 50% wt 8nO›/InzQs NWS gas seIso versus time

at difterent power of 300, 500 and 700 wW (RT) (a) and the timetion of response with

concentration H-S gas (b) 39

Figure 3.9 The response ot self-heated 80% wt SnOv/br-Os NW gas sensor versus time

at difterent power of 300, 500 and 700 ,W (RT) (a) and the fimetion of response with

concentration H-S gas (b) - 40

Figure 3.10 Response and heating power graph of four fabricated sensors 4L

Figure 3.11 The response of self-heated 80% wt SnOyIn-O: NWWs gas sensor versus

time at different tempcrature of 200°C, 250 °C, 300 °C and 350 °C and the function of

Figtwe 3.12 Rssponse characferistic of [nsO; ~ nanowires gas sensor toward 5 ppm 11:5

ITIMS

Nanowires,

ppb ppm

International Training Institute for Malcrials Seicnes

NWs Parts per billion Parts per million

Ra

Ras

Sensitivity Scanning Electron Microscope Transition Fleetron Microscope Volatile Organic Compounds

vi

Figure 3.14 Response to HS of the 80% w1 SnO2/i2O; NWs sensor used sel Heating

effect (Orange Tine) and seisor using the external heater at 200 °C (Blue linc) 44 Figure 3.15 Stability of sensor A External healer B Sel healed made 45 Figure 3.16 Selectivity of ImaO; NWS gas sensor toward NIIs, Ethanol and Il:S gas

Figuue 3.17 IsO› malcrisl H›§ ga sensing mechaniste -4?

L Foundation of the {hesis ) cnmsesenmmonenenneititnieiannemnsnnne

1.3.1 InsOs mmafeTiali, smmosninineniminienmenmnesnnndd 1.3.2, InsOs nanowires I 2aS SEMSOT «sess sesssinnse sented

LA, Hazardous properties of H:$ 285 vaesscsesnomtnsnesintns nasntninssntntmnnnenned

CHAPTER 2 EXPERIMENTAL APPROACH

2.1 Synthesis of In:O nangwirvs is non re seo

s for gas sensing application [1] 5

Figure 1.3 Sensing mechanism of metal oxide based gas scnsor [ ]

Figure 1.4, Power consumption and wrnperature characterized of Hwang WI's micro

tientcr [B| sec

Figure 1.5 Sung Chung Gwiy, Jac-Min Young graup’s micro heater [9] 9

Figure 1.7, Single SuO; NW conlacied with electron beam assisted platinum deposition ina four probes configuration before (2) and after (b) a few hours of operating in sclf-

Figure 2.5 Procadure of scli-heated InOs NWs based gas sensor 28 Figure 2.6, Gas sensitive measuring system at ITIMS (A), Diagram of the gas measuring

Figure 3.1 Menphotogy and snicrostructure of three eomposite simples at (A),(BY 0%: (C)CDY: 20 %, (ECE): 30 %; (G),CHD: 80 % mass ratio of Sn_ were observed by SEM

vũ

2.1.1 Fanipment and chemical

2.2 Fabrication of InzO; nanowires

CHAPTER 3 RESULT AND DISCUSSION

3.1 Morphology of Indium Oxide (In.(:) synthesized by CVD method and In.Os

3.1.1 Effect of Sn proportion on the morphology of Indium Oxide (Ins)

ITIMS

Nanowires,

ppb ppm

International Training Institute for Malcrials Seicnes

NWs Parts per billion Parts per million

Ra

Ras

Sensitivity Scanning Electron Microscope Transition Fleetron Microscope Volatile Organic Compounds

vi

Figure 3.2 Distribution of TsO NWs onto silicon substrate with (A)10 ml (B)20 ml

Tigure 3.3 SEM nnage oŸTroO; nanowires dispersion em the eleelrode wi1h various ratio

Figure 3.4 (4D XRD pallern of 0%, 20%, 50 and 80% SnOwIn:03 NWs 34

Figure 3.5 EDX spect um of (A) Pưưe In:Os NW and (B),(C) SnO3/InzOy XW, 35

Tigure 3.6 The respdnse 0Í selÍ-heated TnsO; gas sensor versus time al different power

of 600, 800, 1200, 1200 pW (a) and the function of response with concentration H28

Figure 3.7 The response of sel heated 20% wi, SasiInOs NWs gas somisor versus lime

at different power af 300, 300 and 700 W (RT) (2) and the fimetion of response with concentration Hs§ gas ( Hi rrtereieireiririrrrerreoo.ÖB Figure 3.8 The response ot self-heated 50% wt 8nO›/InzQs NWS gas seIso versus time

at difterent power of 300, 500 and 700 wW (RT) (a) and the timetion of response with

concentration H-S gas (b) 39

Figure 3.9 The response ot self-heated 80% wt SnOv/br-Os NW gas sensor versus time

at difterent power of 300, 500 and 700 ,W (RT) (a) and the fimetion of response with

concentration H-S gas (b) - 40

Figure 3.10 Response and heating power graph of four fabricated sensors 4L

Figure 3.11 The response of self-heated 80% wt SnOyIn-O: NWWs gas sensor versus

time at different tempcrature of 200°C, 250 °C, 300 °C and 350 °C and the function of

Figtwe 3.12 Rssponse characferistic of [nsO; ~ nanowires gas sensor toward 5 ppm 11:5

2.1.1 Fanipment and chemical

2.2 Fabrication of InzO; nanowires

CHAPTER 3 RESULT AND DISCUSSION

3.1 Morphology of Indium Oxide (In.(:) synthesized by CVD method and In.Os

3.1.1 Effect of Sn proportion on the morphology of Indium Oxide (Ins)

Figure 3.2 Distribution of TsO NWs onto silicon substrate with (A)10 ml (B)20 ml

Tigure 3.3 SEM nnage oŸTroO; nanowires dispersion em the eleelrode wi1h various ratio

Figure 3.4 (4D XRD pallern of 0%, 20%, 50 and 80% SnOwIn:03 NWs 34

Figure 3.5 EDX spect um of (A) Pưưe In:Os NW and (B),(C) SnO3/InzOy XW, 35

Tigure 3.6 The respdnse 0Í selÍ-heated TnsO; gas sensor versus time al different power

of 600, 800, 1200, 1200 pW (a) and the function of response with concentration H28

Figure 3.7 The response of sel heated 20% wi, SasiInOs NWs gas somisor versus lime

at different power af 300, 300 and 700 W (RT) (2) and the fimetion of response with concentration Hs§ gas ( Hi rrtereieireiririrrrerreoo.ÖB Figure 3.8 The response ot self-heated 50% wt 8nO›/InzQs NWS gas seIso versus time

at difterent power of 300, 500 and 700 wW (RT) (a) and the timetion of response with

concentration H-S gas (b) 39

Figure 3.9 The response ot self-heated 80% wt SnOv/br-Os NW gas sensor versus time

at difterent power of 300, 500 and 700 ,W (RT) (a) and the fimetion of response with

concentration H-S gas (b) - 40

Figure 3.10 Response and heating power graph of four fabricated sensors 4L

Figure 3.11 The response of self-heated 80% wt SnOyIn-O: NWWs gas sensor versus

time at different tempcrature of 200°C, 250 °C, 300 °C and 350 °C and the function of

Figtwe 3.12 Rssponse characferistic of [nsO; ~ nanowires gas sensor toward 5 ppm 11:5

s for gas sensing application [1] 5

Figure 1.3 Sensing mechanism of metal oxide based gas scnsor [ ]

Figure 1.4, Power consumption and wrnperature characterized of Hwang WI's micro

tientcr [B| sec

Figure 1.5 Sung Chung Gwiy, Jac-Min Young graup’s micro heater [9] 9

Figure 1.7, Single SuO; NW conlacied with electron beam assisted platinum deposition ina four probes configuration before (2) and after (b) a few hours of operating in sclf-

Figure 2.5 Procadure of scli-heated InOs NWs based gas sensor 28 Figure 2.6, Gas sensitive measuring system at ITIMS (A), Diagram of the gas measuring

Figure 3.1 Menphotogy and snicrostructure of three eomposite simples at (A),(BY 0%: (C)CDY: 20 %, (ECE): 30 %; (G),CHD: 80 % mass ratio of Sn_ were observed by SEM

vũ

L Foundation of the {hesis ) cnmsesenmmonenenneititnieiannemnsnnne

1.3.1 InsOs mmafeTiali, smmosninineniminienmenmnesnnndd 1.3.2, InsOs nanowires I 2aS SEMSOT «sess sesssinnse sented

LA, Hazardous properties of H:$ 285 vaesscsesnomtnsnesintns nasntninssntntmnnnenned

CHAPTER 2 EXPERIMENTAL APPROACH

2.1 Synthesis of In:O nangwirvs is non re seo

Figure 3.2 Distribution of TsO NWs onto silicon substrate with (A)10 ml (B)20 ml

Tigure 3.3 SEM nnage oŸTroO; nanowires dispersion em the eleelrode wi1h various ratio

Figure 3.4 (4D XRD pallern of 0%, 20%, 50 and 80% SnOwIn:03 NWs 34

Figure 3.5 EDX spect um of (A) Pưưe In:Os NW and (B),(C) SnO3/InzOy XW, 35

Tigure 3.6 The respdnse 0Í selÍ-heated TnsO; gas sensor versus time al different power

of 600, 800, 1200, 1200 pW (a) and the function of response with concentration H28

Figure 3.7 The response of sel heated 20% wi, SasiInOs NWs gas somisor versus lime

at different power af 300, 300 and 700 W (RT) (2) and the fimetion of response with concentration Hs§ gas ( Hi rrtereieireiririrrrerreoo.ÖB Figure 3.8 The response ot self-heated 50% wt 8nO›/InzQs NWS gas seIso versus time

at difterent power of 300, 500 and 700 wW (RT) (a) and the timetion of response with

concentration H-S gas (b) 39

Figure 3.9 The response ot self-heated 80% wt SnOv/br-Os NW gas sensor versus time

at difterent power of 300, 500 and 700 ,W (RT) (a) and the fimetion of response with

concentration H-S gas (b) - 40

Figure 3.10 Response and heating power graph of four fabricated sensors 4L

Figure 3.11 The response of self-heated 80% wt SnOyIn-O: NWWs gas sensor versus

time at different tempcrature of 200°C, 250 °C, 300 °C and 350 °C and the function of

Figtwe 3.12 Rssponse characferistic of [nsO; ~ nanowires gas sensor toward 5 ppm 11:5

ITIMS

Nanowires,

ppb ppm

International Training Institute for Malcrials Seicnes

NWs Parts per billion Parts per million

Ra

Ras

Sensitivity Scanning Electron Microscope Transition Fleetron Microscope Volatile Organic Compounds

vi

Figure 3.14 Response to HS of the 80% w1 SnO2/i2O; NWs sensor used sel Heating

effect (Orange Tine) and seisor using the external heater at 200 °C (Blue linc) 44 Figure 3.15 Stability of sensor A External healer B Sel healed made 45 Figure 3.16 Selectivity of ImaO; NWS gas sensor toward NIIs, Ethanol and Il:S gas

Figuue 3.17 IsO› malcrisl H›§ ga sensing mechaniste -4?

2.1.1 Fanipment and chemical

2.2 Fabrication of InzO; nanowires

CHAPTER 3 RESULT AND DISCUSSION

3.1 Morphology of Indium Oxide (In.(:) synthesized by CVD method and In.Os

3.1.1 Effect of Sn proportion on the morphology of Indium Oxide (Ins)

LIST OF TABLES Table 1.1 Summary of publication reporting quantitative information about self-heated

‘Table 1.2 Publications reported self- heating effects in gas sensor using metal oxide

Table 3.1: Comparison with previous study at ITIMS with same approach method 44

LIST OF TABLES Table 1.1 Summary of publication reporting quantitative information about self-heated

‘Table 1.2 Publications reported self- heating effects in gas sensor using metal oxide

Table 3.1: Comparison with previous study at ITIMS with same approach method 44

s for gas sensing application [1] 5

Figure 1.3 Sensing mechanism of metal oxide based gas scnsor [ ]

Figure 1.4, Power consumption and wrnperature characterized of Hwang WI's micro

tientcr [B| sec

Figure 1.5 Sung Chung Gwiy, Jac-Min Young graup’s micro heater [9] 9

Figure 1.7, Single SuO; NW conlacied with electron beam assisted platinum deposition ina four probes configuration before (2) and after (b) a few hours of operating in sclf-

Figure 2.5 Procadure of scli-heated InOs NWs based gas sensor 28 Figure 2.6, Gas sensitive measuring system at ITIMS (A), Diagram of the gas measuring

Figure 3.1 Menphotogy and snicrostructure of three eomposite simples at (A),(BY 0%: (C)CDY: 20 %, (ECE): 30 %; (G),CHD: 80 % mass ratio of Sn_ were observed by SEM

vũ

s for gas sensing application [1] 5

Figure 1.3 Sensing mechanism of metal oxide based gas scnsor [ ]

Figure 1.4, Power consumption and wrnperature characterized of Hwang WI's micro

tientcr [B| sec

Figure 1.5 Sung Chung Gwiy, Jac-Min Young graup’s micro heater [9] 9

Figure 1.7, Single SuO; NW conlacied with electron beam assisted platinum deposition ina four probes configuration before (2) and after (b) a few hours of operating in sclf-

Figure 2.5 Procadure of scli-heated InOs NWs based gas sensor 28 Figure 2.6, Gas sensitive measuring system at ITIMS (A), Diagram of the gas measuring

Figure 3.1 Menphotogy and snicrostructure of three eomposite simples at (A),(BY 0%: (C)CDY: 20 %, (ECE): 30 %; (G),CHD: 80 % mass ratio of Sn_ were observed by SEM

vũ

Figure 3.14 Response to HS of the 80% w1 SnO2/i2O; NWs sensor used sel Heating

effect (Orange Tine) and seisor using the external heater at 200 °C (Blue linc) 44 Figure 3.15 Stability of sensor A External healer B Sel healed made 45 Figure 3.16 Selectivity of ImaO; NWS gas sensor toward NIIs, Ethanol and Il:S gas

Figuue 3.17 IsO› malcrisl H›§ ga sensing mechaniste -4?

2.1.1 Fanipment and chemical

2.2 Fabrication of InzO; nanowires

CHAPTER 3 RESULT AND DISCUSSION

3.1 Morphology of Indium Oxide (In.(:) synthesized by CVD method and In.Os

3.1.1 Effect of Sn proportion on the morphology of Indium Oxide (Ins)

LIST OF TABLES Table 1.1 Summary of publication reporting quantitative information about self-heated

‘Table 1.2 Publications reported self- heating effects in gas sensor using metal oxide

Table 3.1: Comparison with previous study at ITIMS with same approach method 44

ITIMS

Nanowires,

ppb ppm

International Training Institute for Malcrials Seicnes

NWs Parts per billion Parts per million

Ra

Ras

Sensitivity Scanning Electron Microscope Transition Fleetron Microscope Volatile Organic Compounds

vi

s for gas sensing application [1] 5

Figure 1.3 Sensing mechanism of metal oxide based gas scnsor [ ]

Figure 1.4, Power consumption and wrnperature characterized of Hwang WI's micro

tientcr [B| sec

Figure 1.5 Sung Chung Gwiy, Jac-Min Young graup’s micro heater [9] 9

Figure 1.7, Single SuO; NW conlacied with electron beam assisted platinum deposition ina four probes configuration before (2) and after (b) a few hours of operating in sclf-

Figure 2.5 Procadure of scli-heated InOs NWs based gas sensor 28 Figure 2.6, Gas sensitive measuring system at ITIMS (A), Diagram of the gas measuring

Figure 3.1 Menphotogy and snicrostructure of three eomposite simples at (A),(BY 0%: (C)CDY: 20 %, (ECE): 30 %; (G),CHD: 80 % mass ratio of Sn_ were observed by SEM

vũ

s for gas sensing application [1] 5

Figure 1.3 Sensing mechanism of metal oxide based gas scnsor [ ]

Figure 1.4, Power consumption and wrnperature characterized of Hwang WI's micro

tientcr [B| sec

Figure 1.5 Sung Chung Gwiy, Jac-Min Young graup’s micro heater [9] 9

Figure 1.7, Single SuO; NW conlacied with electron beam assisted platinum deposition ina four probes configuration before (2) and after (b) a few hours of operating in sclf-

Figure 2.5 Procadure of scli-heated InOs NWs based gas sensor 28 Figure 2.6, Gas sensitive measuring system at ITIMS (A), Diagram of the gas measuring

Figure 3.1 Menphotogy and snicrostructure of three eomposite simples at (A),(BY 0%: (C)CDY: 20 %, (ECE): 30 %; (G),CHD: 80 % mass ratio of Sn_ were observed by SEM

vũ

LIST OF TABLES Table 1.1 Summary of publication reporting quantitative information about self-heated

‘Table 1.2 Publications reported self- heating effects in gas sensor using metal oxide

Table 3.1: Comparison with previous study at ITIMS with same approach method 44

s for gas sensing application [1] 5

Figure 1.3 Sensing mechanism of metal oxide based gas scnsor [ ]

Figure 1.4, Power consumption and wrnperature characterized of Hwang WI's micro

tientcr [B| sec

Figure 1.5 Sung Chung Gwiy, Jac-Min Young graup’s micro heater [9] 9

Figure 1.7, Single SuO; NW conlacied with electron beam assisted platinum deposition ina four probes configuration before (2) and after (b) a few hours of operating in sclf-

Figure 2.5 Procadure of scli-heated InOs NWs based gas sensor 28 Figure 2.6, Gas sensitive measuring system at ITIMS (A), Diagram of the gas measuring

Figure 3.1 Menphotogy and snicrostructure of three eomposite simples at (A),(BY 0%: (C)CDY: 20 %, (ECE): 30 %; (G),CHD: 80 % mass ratio of Sn_ were observed by SEM

vũ