A method for fabricating an integrated MEMS device and the resulting structure therefore. A control process monitor comprising a MEMS membrane cover can be provided within an integrated CMOS-MEMS package to monitor package leaking or outgassing. The MEMS membrane cover can separate an upper cavity region subject to leaking from a lower cavity subject to outgassing. Differential changes in pressure between these cavities can be detecting by monitoring the deflection of the membrane cover via a plurality of displacement sensors. An integrated MEMS device can be fabricated with a first and second MEMS device configured with a first and second MEMS cavity, respectively. The separate cavities can be formed via etching a capping structure to configure each cavity with a separate cavity volume. By utilizing an outgassing characteristic of a CMOS layer within the integrated MEMS device, the first and second MEMS cavities can be configured with different cavity pressures.