Detection and mitigation of particle contaminants in MEMS devices
First Claim
1. A method for detecting particle contaminants in an integrated circuit device having a device structure and a sense node adjacent to the device structure, and having a particle detecting controller coupled to the device structure and the sense node, the method comprising:
- during an operational mode;
configuring and operating the particle detecting controller to set impedance of the sense node to a predetermined operational mode impedance value,and during a test mode;
configuring and operating the particle detecting controller to set impedance of the sense node to a predetermined test mode impedance value higher than the predetermined operational mode impedance value, to place a test signal on the device structure, and to monitor the sense node for leakage current from the device structure, thereby detecting particles in the integrated circuit device.
1 Assignment
0 Petitions
Accused Products
Abstract
Detecting and/or mitigating the presence of particle contaminants in a MEMS device involves including MEMS structures that in normal operation are robust against the presence of particles but which can be made sensitive to that presence during a test mode prior to use, e.g., by switching the impedance of sensitive structures between an exceptionally sensitive condition during test and a normal sensitivity during operation; surrounding sensitive nodes with guard elements that are at the same potential as those nodes during operation, thereby offering protection against bridging particles, but are at a very different potential during test and reveal the particles by their resulting leakage currents; extending the sensitive nodes to interdigitate with or otherwise extend adjacent to the guard structures, which neither contribute to nor detract from the device operation but cover otherwise open areas with detection means during test; and/or converting benign areas in which particles might become trapped undetectably by electric fields during test to field-free regions by extending otherwise non-functional conductive layers so that the particles can then be moved into detection locations by providing some mechanical disturbance.
24 Citations
22 Claims
-
1. A method for detecting particle contaminants in an integrated circuit device having a device structure and a sense node adjacent to the device structure, and having a particle detecting controller coupled to the device structure and the sense node, the method comprising:
-
during an operational mode; configuring and operating the particle detecting controller to set impedance of the sense node to a predetermined operational mode impedance value, and during a test mode; configuring and operating the particle detecting controller to set impedance of the sense node to a predetermined test mode impedance value higher than the predetermined operational mode impedance value, to place a test signal on the device structure, and to monitor the sense node for leakage current from the device structure, thereby detecting particles in the integrated circuit device. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8)
-
-
9. An integrated circuit device comprising:
-
a device structure; a sense node adjacent to the device structure; and a particle detecting controller coupled to the device structure and the sense node, the particle detecting controller having at least two modes of operation, the modes of operation comprising; an operational mode in which the controller configures and operates circuitry that sets impedance of the sense node to a predetermined operational mode impedance value; and a test mode in which the controller configures and operates circuitry that sets impedance of the sense node to a predetermined test mode impedance value higher than the predetermined operational mode impedance value, configures and operates circuitry that places a test signal on the device structure, and configures and operates circuitry that monitors the sense node for leakage current from the device structure, thereby detecting particles in the integrated circuit device. - View Dependent Claims (10, 11, 12, 13, 14, 15, 16)
-
-
17. A MEMS device comprising:
-
a fixed sense electrode; a guard structure adjacent to the fixed sense electrode; and a controller coupled to the fixed sense electrode and the guard structure, the controller having at least two modes of operation, the modes of operation comprising; an operational mode in which the controller configures and operates circuitry that places the guard structure at the same electrical potential as the fixed sense electrode; and a test mode in which the controller configures and operates circuitry that places the guard structure at a different electrical potential than the fixed sense electrode and configures and operates circuitry that monitors the fixed sense electrode for leakage current from the guard structure, thereby detecting particles in the MEMS device. - View Dependent Claims (18, 19, 20, 21, 22)
-
Specification