Abstract:
Methods and apparatuses are provided for evaluating or testing stiction in Microelectromechanical Systems (MEMS) devices utilizing a mechanized shock pulse generation approach. In one embodiment, the method includes the step or process of loading a MEMS device, such as a multi-axis MEMS accelerometer, into a socket provided on a Device-Under-Test (DUT) board. After loading the MEMS device into the socket, a series of controlled shock pulses is generated and transmitted through the MEMS device utilizing a mechanized test apparatus. The mechanized test apparatus may, for example, repeatedly move the DUT board over a predefined motion path to generate the controlled shock pulses. In certain cases, transverse vibrations may also be directed through the tested MEMS device in conjunction with the shock pulses. An output of the MEMS device is then monitored to determine whether stiction of the MEMS device occurs during each of the series of controlled shock pulses.
Abstract:
A system for testing pressure sensors on a device wafer includes a tray for holding the device wafer. The tray includes a base having a surface, a spacer extending from the surface, and a tacky material disposed on the surface. The spacer holds the device wafer spaced apart from the surface of the base to form a chamber between the surface and the device wafer. A wafer chuck retains the tray and the device wafer under vacuum. The system further includes a nozzle and a seal element in fixed engagement with the nozzle. The seal element surrounds the outlet of the nozzle and is adapted for mechanical contact with the device wafer. An actuator is configured to place the nozzle and a diaphragm of one of the pressure sensors in proximity to one another, wherein a pneumatic pressure stimulus is applied to the diaphragm via an outlet of the nozzle.
Abstract:
A method for testing a plurality of pressure sensors on a device wafer includes placing a diaphragm of one of the pressure sensors on the device wafer in proximity to a nozzle of a test system. A pneumatic pressure stimulus is applied to the diaphragm via an outlet of the nozzle and a cavity pressure is measured within a cavity associated with the pressure sensor in response to application of the pneumatic pressure stimulus. The pneumatic pressure stimulus within the cavity corresponds to the pressure applied to the diaphragm. Methodology is executed to test the strength and/or stiffness of the diaphragm. Additionally, the methodology and test system can be utilized to determine an individual calibration factor for each pressure sensor on the device wafer.