IEC 62047-37-2020 pdf free download

IEC 62047-37-2020 pdf free download.Semiconductor devices — Micro-electromechanical devices — Part 37: Environmental test methods of MEMS piezoelectric thin films for sensor application
Dispositifs a semiconducteurs — Dispositifs microélectromécaniques — Partie 37: Méthodes d’essai d’environnement des couches minces piézoélectriques MEMS pour les applications de type capteur.
As a general rule, final measurements shall be conducted within 48 h from the completion of tests after verifying that the surface of the DUT is dry. When conducting intermediate measurements prior to the final measurements, the DUT shall be deposited back into the testing chamber within 96 h after being removed for measurements. Final measurements are preferably completed within 96 h after halting voltage application to the DUT.
5 Environmental and dielectric withstand testing
5.1 Environmental testing
5.1.1 General
Equipment used in these experiments includes:
• a chamber or a room capable of maintaining predetermined test temperature and humidity and allowable temperature and humidity;
• a vibrator or an external actuator for generating a predetermined deflection of the unimorph beam;
• a mechanical stress and strain, or vibration, application equipment having sufficient resistance for withstanding the test temperatures and humidity.
The chamber shall be capable of maintaining its entire interior at the set temperature ±2 °C and the set humidity ±5 % during the test. The applied mechanical stress and strain, and the operating method shall be established with consideration for the limits of the DUT. The application circuit shall be considered to account for load conditions and other factors in order that the operating state of the OUT be suitably maintained.
NOTE 1 The degree of degradation in a device under test (DUT) is evaluated by measuring the piezoelectric properties of the OUT before and after applying the environmental stress of temperature and humidity.
NOTE 2 The degree of degradation in a OUT is evaluated using the measurement methods in IEC 62047-30.
5.1.2 High-temperature bias test
The objective of this test is to evaluate the ability of MEMS piezoelectric thin film to operate at a high temperature. Mechanical stress and strain (beam deflection) is applied to the piezoelectric film under a high temperature to evaluate the effects of these conditions over a long duration. The conditions applied to the DUT, including the vibration mode (resonant mode or non-resonant mode), input waveform, the frequency, and the like shall be determined based on the expected application of the sensor. The following test conditions shall be applied:
• test temperature: 85 °C or higher;
• test duration: 96 h or longer.
The example of this test result is provided in Annex A.
NOTE I Sample test temperatures can include 85 °C, 105 °C and 125 C.
NOTE 2 Sample test durations can include 96 h. 480 h and 960 h.
5.1.3 High-temperature and high-humidity bias test
The objective of this test is to evaluate the ability of MEMS piezoelectric thin film to operate under high temperature and high humidity. Mechanical stress and strain (beam bending) is applied to the piezoelectric thin film under high temperature and humidity and the effects of these conditions are assessed over a long duration. The humidity test determines whether electronic products have sufficient electrical and mechanical properties to withstand heavy conditions with high relative humidity, regardless of whether condensation is present. The humidity test may also be used to inspect the resistance of the DUT to various corrosive actions. Based on the expected application of the sensor, the measurement parameters shall be determined as follows:
• resonant mode or non-resonant mode;
• input waveform;IEC 62047-37-2020 pdf free download.