ABSTRACT
The second volume of Handbook of Humidity Measurement "Electronic and Electrical Humidity Sensors" is entirely devoted to the consideration of different types of solid-state devices which can be used for humidity measurement. There is given a detailed information, including advantages and disadvantages about the capacitive, resistive, gravimetric, hygrometric, field ionization, microwave, solid-state electrochemical, and thermal conductivity-based humidity sensors, followed by a relevant analysis of the properties of humidity-sensitive materials, used for the development of such devices. Humidity sensors based on thin film and field-effect transistors, heterojunctions, flexible substrates, and integrated humidity sensors are also discussed in this volume. Great attention is also paid to the consideration of conventional devices, which were used for the measurement of humidity for several centuries. It is important to note that many of these methods are widely used so far.
Introduction in Humidity Sensors. Introduction in electronic and electrical humidity sensors. Conventional Methods and Brief History of Humidity Measurements. Gravimetric method of humidity measurement. Mechanical (hair) hygrometer. Psychrometer. Chilled mirror hygrometer or mirror-based dew-point sensors. Heated salt-solution method for humidity measurement. Electrolytic or coulometric hygrometers. Humidity measurement based on Karl Fischer titration. Other conventional methods of humidity measurement. Electronic and Electrical Humidity Sensors and Basic Principles of their Operation. Сapacitance-based humidity sensors. Resistive humidity sensors. Gravimetric humidity sensors. Cantilever- and membrane-based humidity sensors. Thermal conductivity-based hygrometers. Field ionization humidity sensors. Humidity sensors based on thin film and field-effect transistors. Hetero-junction-based humidity sensors. Kelvin probe as a humidity sensor. Solid state electrochemical humidity sensors. New Trends and Outlook. Microwave-based humidity sensors. Integrated humidity sensors. Humidity sensors on flexible substrate. Non-traditional approaches to humidity measurement. Summary and outlook.
