Patent ID: 8007166

Claim:
A method for testing wafer bond line width in a MEMS device, the MEMS device having at least a first and second wafer layer with a bond line between each wafer layer, the method comprising the steps of: exposing the MEMS device to a vaporized fluid for a predetermined time period at a first temperature, within a range of temperatures for evaporating the fluid; cooling the MEMS device to a second temperature, within a range of temperatures for freezing the fluid; testing the MEMS device by operating the device at a third temperature, within a range of temperatures for freezing the fluid, to determine if there is discontinuity in the performance of the device during operation of the device; if there is no discontinuity in performance during operation of the MEMS device, reducing the bond line width; exposing the MEMS device with the reduced bond line width to a vaporized fluid for a predetermined time period at the first temperature for evaporating the fluid; cooling the MEMS device to the second temperature for freezing the fluid; and operating the MEMS device at the third temperature for freezing the fluid in order to determine if there is discontinuity in performance of the device during operation; wherein presence or absence of a discontinuity in performance during operation of the MEMS device indicates the wafer bond line is leaking, or is not leaking, respectively.