Method for optimizing direct wafer bond line width for reduction of parasitic capacitance in MEMS accelerometers
AssigneeNorthrop Grumman Systems Corporation
InventorsHenry C. Abbink, Gabriel M. Kuhn, Howard Ge, Daryl Sakaida
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Abstract
A method for optimizing direct wafer bond line width for reduction of parasitic capacitance in a MEMS device by reducing the width of a bond line between a first and a second wafer, exposing the MEMS device to a water vapor for a predetermined time period and at a first temperature capable of evaporating water, cooling the MEMS device at a second temperature capable of freezing the water, and operating the MEMS device at a third temperature capable of freezing the water to determine if there is discontinuity during operation.
Claims12
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.
Dependencies are inferred from the claim text.