4 4 6 8 1 9 A7 B7 五、發明説明（） —、發明背景 濕度是指大氣中含水汽的多寡，科學的作法是量測某一溫度下的水蒸氣4 4 6 8 1 9 A7 B7 V. Description of the invention ()-Background of the invention Humidity refers to the amount of water vapor in the atmosphere. The scientific method is to measure the water vapor at a certain temperature.
- i&iiM ------------ο衣！ (請先聞讀背面之注##·項再填寫本頁) 是人們對週遭環境相當敏感的因素溫度越高飽和蒸氣壓越大，露點溫度則是 指溫度下降至水汽開始溫度。_的測量方法有多種"：⑴毛髮、 纖維伸張的機械法’（2池學藥品吸水法，(3)乾濕球法，⑷露點法，⑸石英振 盪法’⑹紅外線吸收法等多種❶它們的缺點不外是反應慢(1、2、3、4)，不精準 (1、2),組件複雜(5、6),價格昂貴(4、5、6)，体積龐大(以上皆是卜由於科技 的突飛猛進，過去認爲不切實際的熱導式測量濕度方法，已到實用的階段， 而且可以針對上述缺失，作一綜合性的改善。 參考文獻： 1. K. Carr-Brion, MMoisture Sensors in Process Contror, Elsevier Applied Science Publishers (1986). 2. R. E. RusJdn, ed., humidity and Moisture", Vol. 1, Reinhold, N. YM 1965. 3. J. H. Arnold, Physics, 4 pp. 255-262, pp. 334-340,1993. 4. H. A. Willis, **Advance in Infra Red and Raman SpectroscopyT,, Vol 12 pp. 81-135, 1976. 5. B. E. Dunn，’’Advances in Instrumentation’’，27 pp.1-5 1972, 6. R. Villalobos, Analytical Chemistry, 47 pp983A-1004A, 1975. 經濟部中央標莘局員工消費合作社印製 7. A. P. Hanison, UK Patent Application 2130739 1984. 8. D. M. Rosie and E F, Barrie, J. Chromatog. Sci., pp. 237-250 1973. 二、發明目的 以成熟的微加工技術尋找新的濕度量測技術及製作方法，以利改善前述 之諸項缺失》 本紙張尺度適用中國國家榡準（CNS ) Λ4规格（21〇Χ 297公釐） 經濟部中央標準局負工消費合作社印掣 4468 1 9 Λ7 Β7 五、發明説明（） 三、 發明特性 不同濕度下的氣体熱導係數不一，電熱線的散熱速率因而有異，其電阻 的變化量也隨著有些微差別，此現象可以用來測量大氣的濕度：配合微加工技 術，則可達到微小化的目的。 四、 發明內容 氣体的熱導係數，在平均自由徑遠小於兩傳熱体之間距時，和其分子量 的平方根成反比，但和壓力無關。空氣的平均分子量爲29，水的分子量爲18， 兩者混合体的導熱係數也因水汽含量的多寡而異。利用此一特性，電熱線的散 熱速率因而有異。金屬的電阻係數是溫度的函數，溫度越高，電阻越大，故熱 電阻線受到氣体導觀數的差異，電阻也含有些微的改變* 測量電阻最敏感而且簡易的方法乃惠氏電橋，其原理如圖1所示。當電 橋在平衡狀態時，即RoRfR^ ,沒有電流通過電位計。當其中的感測電阻〜 改變時，惠氏電橋平衡被破壞，電位計即感測到電流的通過，由此可測得電阻 的改變量。 根據上述原理，本發明提出如圖2之濕度感測器構想。如圖2所示，201 至204爲惠氏電橋之四支電阻，該電阻線以薄膜技術鍍在絕熱基材205上(圖3); 22卜228爲電阻之引線，供惠氏電橋之佈線及電流之輸入；214爲大氣通道，215 爲密閉氣室，通以約0.5大氣壓之乾燥空氣。當電橋通入電流加熱電阻達到一 定溫度時，201及202即成爲濕度之探針，203和204則爲參考電阻。由於不同 濕度下的散熱速率不一，201和202即產生不同於203和204的電阻改變量，電 橋因而失去平衡，其訊號由惠氏電橋之電位計量測，經適當的校正後，即可測 出大氣的相對濕度》探測電阻基本上只須惠氏電橋之一支即可，上述201及202 兩支電阻均用於探測之用，可增加靈敏度~倍8 ’如圖4所示。相對濕度必須 配合溫度的量測，才有實際的意義。利用金屬電阻的改變於溫度之量測，已相 本纸張尺度適用中國國家標準（CNS ) A4規格（2!〇Χ2ί»7公釐） L----------°裝-----：--訂— — _ (請先閱讀背面之注意事項再填寫本頁) » —^1 - - . I— f^i nf 經濟部中央標準局員工消費合作社印製 A7 B7 五、發明説明（） 當普遍。吾人可在濕度感測器晶片上找—適當位置’另鍍一對溫度敏感的薄膜 電阻220於熱氧化層219上（圖3) ’即可作爲臟感測器。氧化層之目的有二： ⑴矽爲半導體，氧化砂則爲絕緣層可以避免電阻線的不當干擾，⑵氧化砂亦 爲絕熱層*可以隔離感測器的熱傳。實際上’任何有上述作用之塗層均可適用， 如Si3N4、pdyimide等。該薄膜電阻曝露於大氣，不須通電加熱。如此結合溫、 濕度感測器均在一晶片上完成，更可達到精細的目的。 由於矽晶之微加工技術已成熟，故以此材料爲例說明。矽晶爲良好之熱 導体，圖3爲濕度感測器薄膜電阻通大氣之半部，所示空穴216之作用在避免 广矽晶之散熱2濕度感測器薄膜電阻密閉之半部亦有相同之構造(未圖示）9 205絕 熱薄膜則有減低散熱之作用；218爲砂晶材料之上蓋板，事先作好氣体通道及 密閉氣室之蝕刻，然後和下蓋板對位後接合，即完成以惠氏電橋及矽晶微加工 技術製程之濕度感測[器》 實施例: 利用本熱導式濕度感測器，當電橋通入電流加熱電阻達到一定溫度時，先 讀取已知濕度的空氣，在不同溫度下的電位差値，並製作成校正曲線如圖5所 示，再將此校正曲線輸入微電腦中儲存。當量測未知環境的濕度時，微電腦可 根據校正曲線及利用內插方式，將電位計上的電位差値及溫度感測器上的溫度 値，直接轉換成濕度。由於本熱導式濕度感測器所獲得的溫濕度値，均爲數位 訊號，如配合加濕、除濕設備及空調設備，可應用於環境溫濕度自動調節。 圖式說明： 圖1.惠氏電橋示意圓 圖2.利用微細加工技術製作惠設計圖 圖3.熱導式濕度感測器設計圖 本紙張尺度適用中國國家插準（CMS ) A4规格（210 X 297公釐） ----------ο裝— (請先閱讀背面之注意事項再填寫本頁)-i & iiM ------------ ο clothing! (Please read the note ## · item on the back before filling this page) It is a factor that people are quite sensitive to the surrounding environment. The higher the temperature, the higher the saturated vapor pressure, and the dew point temperature means the temperature drops to the starting temperature of water vapor. There are a variety of measurement methods: "Mechanical method of hair and fiber extension" (2 Chihsu Pharmaceutical Water Absorption Method, (3) Wet and Dry Bulb Method, ⑷Dew Point Method, ⑸Quartz Oscillation Method, ⑹Infrared Absorption Method, and many other methods Their disadvantages are slow response (1,2,3,4), inaccurate (1,2), complex components (5,6), expensive (4,5,6), and large size (all of the above are Due to the rapid advancement of science and technology, the thermal conductivity method of humidity measurement, which was considered impractical in the past, has reached the practical stage, and can be comprehensively improved to address the above shortcomings. References: 1. K. Carr-Brion, MMoisture Sensors in Process Contror, Elsevier Applied Science Publishers (1986). 2. RE RusJdn, ed., Humidity and Moisture ", Vol. 1, Reinhold, N. YM 1965. 3. JH Arnold, Physics, 4 pp. 255- 262, pp. 334-340, 1993. 4. HA Willis, ** Advance in Infra Red and Raman SpectroscopyT ,, Vol 12 pp. 81-135, 1976. 5. BE Dunn, `` Advances in Instrumentation '', 27 pp.1-5 1972, 6. R. Villalobos, Analytical Chemistry, 47 pp983A-1004A, 1975. Ministry of Economic Affairs Printed by the Consumer Standards Cooperative of the Central Bureau of Standards 7. AP Hanison, UK Patent Application 2130739 1984. 8. DM Rosie and EF, Barrie, J. Chromatog. Sci., Pp. 237-250 1973. 2. The purpose of the invention is mature Micro-processing technology to find new humidity measurement technology and production methods to improve the above-mentioned deficiencies "This paper size is applicable to China National Standards (CNS) Λ4 specifications (21〇 × 297 mm) Industrial and consumer cooperatives' seals 4468 1 9 Λ7 B7 V. Description of the invention (3) Invention characteristics The gas has different thermal conductivity coefficients under different humidity, and thus the heat dissipation rate of the electric heating wire is different, and the amount of change in its resistance also varies slightly. Difference, this phenomenon can be used to measure the humidity of the atmosphere: with the micro-processing technology, it can achieve the purpose of miniaturization. 4. Summary of the Invention The thermal conductivity of a gas is inversely proportional to the square root of its molecular weight when the average free path is much smaller than the distance between two heat transfer bodies, but it has nothing to do with pressure. The average molecular weight of air is 29 and the molecular weight of water is 18. The thermal conductivity of the mixture of the two also varies depending on the water vapor content. With this characteristic, the heat radiation rate of the heating wire is different. The resistivity of a metal is a function of temperature. The higher the temperature, the greater the resistance. Therefore, the thermal resistance line is subject to the difference in the gas observation number. The resistance also contains some slight changes. * The most sensitive and simple method of measuring resistance is the Wyeth bridge. The principle is shown in Figure 1. When the bridge is in equilibrium, RoRfR ^, no current flows through the potentiometer. When the sense resistance is changed, the balance of the Wyeth bridge is broken, and the potentiometer senses the passage of current, so that the change in resistance can be measured. Based on the above principles, the present invention proposes the concept of a humidity sensor as shown in FIG. 2. As shown in Figure 2, 201 to 204 are the four resistors of the Wyeth bridge. The resistance wire is plated on a heat-insulating substrate 205 using a thin film technology (Figure 3); 22 and 228 are the leads of the resistor for the wiring of the Wyeth bridge. And current input; 214 is an atmospheric channel, and 215 is a closed air chamber, which is passed with dry air of about 0.5 atm. When the bridge heating current reaches a certain temperature, 201 and 202 become humidity probes, and 203 and 204 are reference resistances. Due to the different heat dissipation rates under different humidity, 201 and 202 will produce different resistance changes than 203 and 204, and the bridge will be out of balance. The signal is measured by the potential of the Wyeth bridge. After proper correction, The relative humidity of the atmosphere can be measured. "The detection resistor basically requires only one branch of the Wyeth bridge. Both of the above 201 and 202 resistors are used for detection, which can increase the sensitivity ~ 8 times as shown in Figure 4. Relative humidity must be matched with temperature measurement to have practical significance. Utilizing the change of the metal resistance to the temperature measurement, the paper size has been adapted to the Chinese National Standard (CNS) A4 specification (2! 〇Χ2ί »7 mm) L ---------- ° pack-- ---: --Order — — _ (Please read the notes on the back before filling out this page) »— ^ 1--. I— f ^ i nf Printed by the Consumers' Cooperative of the Central Standards Bureau of the Ministry of Economic Affairs A7 B7 5. Description of the invention () When universal. I can find it on the humidity sensor chip-at a proper position 'and plate a pair of temperature-sensitive film resistors 220 on the thermal oxide layer 219 (Fig. 3)' to serve as a dirty sensor. The purpose of the oxide layer is twofold: osmium silicon is a semiconductor, and oxidized sand is an insulating layer to avoid undue interference of resistance wires, and dysprosium oxide is also a thermal insulation layer * to isolate the heat transfer of the sensor. In fact, any coating that has the above effects can be applied, such as Si3N4, pdyimide, and so on. The film resistor is exposed to the atmosphere and does not need to be heated by electricity. In this way, the temperature and humidity sensors are combined on a single chip to achieve a finer purpose. As the microfabrication technology of silicon crystal has matured, this material is used as an example. Silicon crystal is a good thermal conductor. Figure 3 shows the half of the humidity sensor film resistance passing through the atmosphere. The hole 216 shown in the figure is used to avoid heat dissipation from the wide silicon crystal. 2 The sealed half of the humidity sensor film resistance also has The same structure (not shown) 9 205 insulation film can reduce the heat dissipation; 218 is the top cover of the sand crystal material, and the gas channel and the closed air chamber are etched beforehand, and then aligned with the lower cover and joined That is, the humidity sensor [device] manufactured by the Wyeth bridge and the silicon micro-processing technology is completed. Example: Using this thermal conductivity humidity sensor, when the heating resistance of the current through the bridge reaches a certain temperature, read it first. The potential difference at different temperatures of air with known humidity is made into a calibration curve as shown in Figure 5, and this calibration curve is input into a microcomputer for storage. When measuring the humidity in an unknown environment, the microcomputer can directly convert the potential difference 値 on the potentiometer and the temperature 上 on the temperature sensor according to the calibration curve and the interpolation method into humidity. Because the temperature and humidity 获得 obtained by this thermal conductivity type humidity sensor are all digital signals, they can be used to automatically adjust the temperature and humidity of the environment when used with humidification, dehumidification equipment and air conditioning equipment. Schematic description: Figure 1. Schematic circle of Wyeth bridge. 2. Design of Wyeth design using micro-processing technology. X 297 mm) ---------- ο equipment— (Please read the precautions on the back before filling this page)
-V 經濟部中央標準局員工消費合作社印製 4 4 6 8 A7 __^_B7_ 五、發明説明（） 圖4.熱導式濕度感測器惠氏電橋示意圖 圖5濕度校正曲線示意圖 圖號說明： 心、艮、R2、R3惠氏電橋上四個電阻 201〜204利用薄膜技術製作惠氏電橋上四個電阻 221〜228惠氏電橋上電阻之引線 214大氣通道 215密閉氣室 205絕熱基材 219熱氧化層 217、218矽晶材料 220溫度感測薄膜 216空穴設計作用在避免砂晶之散熱 本紙張尺度適用中國國家標準（CNS ) Α4規格（210Χ297公釐） -------------,Γ 袈-----—訂丨·-----/'I--------------;___ (請先閱讀背面之注意事項再填寫本頁〕-V Printed by the Consumer Cooperatives of the Central Standards Bureau of the Ministry of Economic Affairs 4 4 6 8 A7 __ ^ _ B7_ V. Description of the invention () Figure 4. Schematic diagram of Wyeth bridge of thermal conductivity humidity sensor Figure 5 Schematic diagram of humidity calibration curve Heart, Gen, R2, R3 Four resistors on Wyeth bridge 201 ~ 204 Using thin film technology to make four resistors on Wyeth bridge 221 ~ 228 Leads on resistors on Wyeth bridge 214 Atmospheric channel 215 Closed air chamber 205 Thermal insulation substrate 219 Thermal oxidation layer 217, 218 silicon material 220 temperature sensing film 216 cavity design function to avoid heat dissipation of sand crystal The paper size is applicable to China National Standard (CNS) A4 specification (210 × 297 mm) ----------- -, Γ 袈 ------- Order 丨 · ----- / 'I --------------; ___ (Please read the notes on the back before filling this page A