열산화법으로 형성한 $Pt-SnO_{2-x}$ 박막소자의 CO 가스 감지특성

심창현,박효덕,이재현,이덕동,Shim, Chang-Hyun,Park, Hyo-Derk,Lee, Jae-Hyun,Lee, Duk-Dong 한국센서학회 1992 센서학회지 Vol.29 No.3

적층구조의 Pt-Sn 박막을 히터 위에서 열산화하여 $Pt-SnO_{2-x}$ 박막형 CO 가스감지소자를 제조하였다. 열증착법으로 증착된 Sn의 두께는 $4000{\AA}$이었으며 그 위에 D.C. sputtering법으로 증착된 Pt의 두께는 $14{\AA}{\sim}71{\AA}$ 이었다. XRD 분석에서 $Pt-SnO_{2-x}$ 박막은 $200{\AA}$ 정도의 입경과 주방향성이 (110)인 $(SnO_{2}){\cdot}6T$ 결정상을 보였다. $Pt-SnO_{2-x}$ 박막소자(Pt 두께 : $43{\AA}$)는 6000 ppm의 CO에 대해 80% 정도의 감도와 CO에 대해 높은 선택도를 나타내었다. 그리고 CO에 고감도를 갖는 $Pt-SnO_{2-x}$ 박막소자의 열산화 온도와 동작온도가 각각 $500^{\circ}C$와 $200^{\circ}C$이었다. $Pt-SnO_{2-x}$ thin film sensing devices has been fabricated by thermal oxidation of stacked Pt-Sn thin film on the heater. The thickness of Sn thin film deposited by thermal evaporation was $4000{\AA}$ and the thickness of Pt deposited by D. C. sputtering on Sn thin film was $14{\sim}71{\AA}$ range. The XRD analysis show that the $Pt-SnO_{2-x}$ thin films are formed by grains with a diameter of about $200{\AA}$ randomly connected and the crystalline phase of the thin films are preferentally oriented in the (110) direction. $Pt-SnO_{2-x}$ thin film device (Pt thickness : $43{\AA}$) to 6000 ppm CO shows the sensitivity of 80% and high selectivity to CO. And the operating temperature and the thermal oxidation temperature of $Pt-SnO_{2-x}$ thin film device with high sensitivity to CO were $200^{\circ}C$ and $500^{\circ}C$, respectively.

CH3CN 감지를 위한 SnO2/Al2O3/Pd 후막소자의 제조 및 그 특성

박효덕,조성국,손종락,이덕동 ( Hyo Derk Park,Sung Guk Jo,Jong Rack Sohn,Duk Dong Lee ) 한국센서학회 1992 센서학회지 Vol.1 No.1

The optimum base material was selected by the thermal decomposition temperature of CH₃CN on the surface of various metal oxides, and the FT-IR analyses of its products. On the surface of SnO₂, CH₃CN was initiated to decompose at 130℃ and produced a lot of products at 200℃. The products from the reaction were found to be H₂O, NIA, and CO, but N₂O has started to produce at 320℃. The sensing characteristics of SnO₂ sensor to CH,CN are influenced by the absorbed species which are produced by the oxidation reaction of CH₃CN on the surface of metal oxide. The gaseous species produced from the surface of sensing material in the oxidation reaction were found to be CO, NH₃, H₂O and NO, etc.. It was assumed that the amount of N0, play a great role to the determining sensing properties. In the condition of 170 ppm CH₃CN, the sensitivity and optimum operating temperature of SnO₂ were 70% and 300℃, respectively. In this research, the response time of CH₃CN to SnO₂/Al₂O₃/Pd sensor added with 0.2 wt% Pd was found about 10 sec and sensitivity was also found relatively high.

열산화법으로 형성한 Pt-SnO2-x 박막소자의 CO 가스 감지특성

심창현,박효덕,이재현,이덕동 ( Chang Hyun Shim,Hyo Derk Park,Jae Hyun Lee,Duk Dong Lee ) 한국센서학회 1992 센서학회지 Vol.1 No.1

Pt-SnO(2-x) thin film sensing devices has been fabricated by thermal oxidation of stacked Pt-Sn thin film on the heater. The thickness of Sn thin film deposited by thermal evaporation was 4000 Å and the thickness of Pt deposited by D.C. sputtering on 5n thin film was 14∼71 Å range. The XRD analysis show that the Pt-SnO(2-x) thin films are` formed by grains with a diameter of about 200 Å randomly connected and the crystalline phase of the thin films are preferentally oriented in the (110) direction. Pt-SnO_(2-x) thin film device (Pt thickness : 43 Å) to 6000 ppm CO shows the sensitivity of 80 % and high selectivity to CO. And the operating temperature and the thermal oxidation temperature of Pt-SnO_(2-x) thin film device with high sensitivity to CO were 200℃ and 500℃, respectively.

$CH_{3}CN$ 감지를 위한 $SnO_{2}/Al_{2}O_{3}/Pd$ 후막소자의 제조 및 그 특성

박효덕,조성국,손종락,이덕동,Park, Hyo-Derk,Jo, Sung-Guk,Sohn, Jong-Rack,Lee, Duk-Dong 한국센서학회 1992 센서학회지 Vol.29 No.3

The optimum base material was selected by the thermal decomposition temperature of $CH_{3}CN$ on the surface of various metal oxides, and the FT-IR analyses of its products. On the surface of $SnO_{2}$, $CH_{3}CN$ was initiated to decompose at $130^{\circ}C$ and produced a lot of products at $200^{\circ}C$. The products from the reaction were found to be $H_{2}O$, $NH_{3}$ and CO, but $N_{2}O$ has started to produce at $320^{\circ}C$. The sensing characteristics of $SnO_{2}$ sensor to $CH_{3}CN$ are influenced by the absorbed species which are produced by the oxidation reaction of $CH_{3}CN$ on the surface of metal oxide. The gaseous species produced from the surface of sensing material in the oxidation reaction were found to be CO, $NH_{3}$, $H_{2}O$ and $NO_{x}$ etc.. It was assumed that the amount of $NO_{x}$ play a great role to the determining sensing properties. In the condition of 170 ppm $CH_{3}CN$, the sensitivity and optimum operating temperature of $SnO_{2}$ were 70% and $300^{\circ}C$, respectively. In this research, the response time of $CH_{3}CN$ to $SnO_{2}/Al_{2}O_{3}/Pd$ sensor added with 0.2 wt % Pd was found about 10 sec and sensitivity was also found relatively high. $CH_{3}CN$ 감지를 위한 최적 모물질은 $CH_{3}CN$의 억분해 온도와 생성량을 적외선 흡수 스펙트럼으로부터 비교함으로써 선정되었다. $SnO_{2}$ 표면에서 $CH_{3}CN$은 $130^{\circ}C$에서부터 열분해되기 시작하여 $300^{\circ}C$에서는 많은 양의 생성물을 생성하였다. 산화반응에 의한 $CH_{3}CN$은 $CO_{2}$, $NH_{3}$ 및 $H_{2}O$로 열분해되었으며, $320^{\circ}C$에서부터 $N_{2}O$가 생성되기 시작하였다. $SnO_{2}$ 감지소자의 $CH_{3}CN$에 대한 감지특성은 $CH_{3}CN$과 금속산화물과의 산화반응으로 인해 생성된 흡착종에 의해 영향을 받았다. 감지물질표면과의 반응에서 생성된 흡착종은 CO, $NH_{3}$, $H_{2}O$ 및 $NO_{x}$ 등이었다. $NO_{x}$의 생성량은 감지특성에 큰 영향을 나타냄을 알 수 있다. 170 ppm의 $CH_{3}CN$에 대한 $SnO_{2}$의 감도와 동작온도는 각각 70% 정도와 $300^{\circ}C$이었다. 0.2wt% Pd 첨가된 $SnO_{2}/Al_{2}O_{3}/Pd$ 감지소자는 $CH_{3}CN$에 대해 높은 감도를 나타내었으며, 응답시간은 약 10초이었다.

Tetraethylorthosilicate 용액을 침적시킨 SnO2 후막형 가스감지소자의 아세토니트릴에 대한 선택성

박효덕,조성국,손종락,이덕동 ( Hyo Derk Park,Sung Guk Cho,Jong Rack Sohn,Duk Dong Lee ) 한국센서학회 1993 센서학회지 Vol.2 No.2

The SnO/A1z03/Nbzos thick film devices added with SiO₂ were fabricated by means of the dipping into Si(CzHso)a solution and the sensing characteristics of the thick film devices to CH₃CN vapor was investigated The reaction products of CH₃CN by the heating reaction on the thick film devices were analyzed by the FT-IR method using gas reaction cell. The products of CH₃CN vapor by the surface reaction on the thick film devices were CO₂, H₂O, N₂O and the acids produced from NO_x and H₂O. Optimum processes of the thick film devices were determined by the investigation of the sensing characteristics to CH₃CN vapor. The thick film devices showed high selectivity to CH₃CN vapor and negative sensitivity by oxidizing agents (NO_x) produced during the reaction of CH₃CN vapor on the thick films.

High Sensitivity and Low Power Consumption Gas Sensor Using MEMS Technology and Thick Sensing Film

Nak-Jin CHOI,이덕동,Hyo-Derk PARK,김재창,허증수,박준식,Jun-Hyuk KWAK,Kwang-Bum PARK,Kyu-Sik SHIN 한국물리학회 2004 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.45 No.2

Thick lms based on tin oxide are fabricated on Si substrate and their gas response characteristics for test gas are examined. Sensing materials are added Al2O3 based on SnO2. In general, sensing materials are deposited on alumina substrate because of easy process but this type of sensor has high power consumption. Two heater types using a micromechanical system (MEMS) are designed to reduce the power consumption and are simulated. The sensor consists of one heater, two temperature electrodes and one sensing electrode. Sensor dimensions are 8 mm 8 mm 0.5 mm, and sensing-lm dimensions are 2.7 mm 2.7 mm. Test gas is dimethylmethyl phosphonate (DMMP) gas that is the simulant gas of nerve agent, one of the chemical warfare agents. Sensitivities are measured with dierent amounts of Al2O3, with dierent operating temperatures and with dierent concentrations. High sensitivity is acquired by using thick sensing lm, and low power consumption, 130 mW at 300 C, is achieved by using the MEMS technology.

학술발표회 초록 : ( 촉매 및 반응공학 Poster 발표 ) ; Acetonitrile 감지를 위한 SnO2 소자의 감지특성

조성국(Sung Guk Cho),한종수(Jong Su Han),손종락(Jong Rak Sohn),박효덕(Hyo Derk Park),이덕동(Duk Dong Lee) 한국화학공학회 1992 추계학술발표회 Vol.- No.-

SnO2 후막소자의 SiO2 첨가제에 의한 감도 특성

이덕동,박효덕,이우일,전춘배,이재현 경북대학교 전자기술연구소 1993 電子技術硏究誌 Vol.14 No.1

The SnO₂/Al₂O₃/Nb₂O_5 thick film devices added SiO₂ were fabricated by dipping, sputtering and addition of powder, respectively. The products of CH₃CN vapor by the oxidation reaction on the thick film devices were CO₂, H₂O, N₂O and nitric acid complex(NO_x and H₂O). From these products, the adsorbed species were thought to be CO, O-H and NO_x. The thick film s added SiO₂ showed the negative sensitivity to CH₃CN vapor by oxidizing agents(NO_x). The devices fabricated by dipping of (G₂H_5O)₄Si solution showed high sensitivity and selectivity to CH₃CN vapor. Optimum added amounts of Nb₂O_5 and operating temperature were 1.0 wt% and 300℃, respectively.

Nb2O5가 첨가된 SnO2 감지소자의 CH3CN 감지특성

이덕동,박효덕,이재현 경북대학교 전자기술연구소 1992 電子技術硏究誌 Vol.13 No.1

Thick film devices based on SnO₂ added with Nb₂O_5(0.2-2.0 wt%) have been fabricated by means of the screen printing method The sensing characteristics of CH₃CN was influenced by the species which were produced by the oxidation reaction between CH₃CN and the surface of metal oxide. The products by the thermal-analysis of CH₃CN were CO₂, NH₃ and H₂O. The absorption species which influence the sensing properties of the thick films were thought to be the complex gases of CO, NH₃ and H₂O(O-H). As an appropriate binder, PVA(polyvinylalcohol) was selected. SnO₂-based sensing devices added Nb^(+5) exhibited the sensitivity of 94% at 300℃, and the selectivity of SnO₂-based devices to CH₃CN was considerably high. The deviation of R_0 of the sensing devices was within ±10%. The thick film devices which maintained for 30 days at 300℃ exhibited R_0 of 25±2㏀ and sensitivity of 84% in 85 ppm CH₃CN ambient.

NO₂감지를 위한 SnO₂후막소자의 제조 및 그 특성

한종수,박효덕,손종락,이덕동 경북대학교 센서기술연구소 1992 센서技術學術大會論文集 Vol.3 No.1