Method and system for fabricating a MEMS device cap

A method comprising:

• depositing a mask over a substrate;
• patterning the mask, wherein a first exposed portion of the patterned mask is associated with a first cavity region positioned between a first and a second standoff regions and a second exposed portion of the patterned mask is associated with a second cavity region positioned between the second and a third standoff regions, and wherein the patterned mask covers the first, the second, and the third standoff regions;
• etching exposed portions of the substrate to form a first cavity within the first cavity region, a second cavity within the second cavity region, wherein a depth of the first cavity is the same as a depth of the second cavity, and wherein the etching further forms a first, a second, and a third standoffs associated with the first, the second, and the third standoff regions respectively;
• depositing a polysilicon layer over the patterned mask and further over a portion of the substrate uncovered by the patterned mask;
• depositing a getter layer over the polysilicon layer;
• patterning the getter layer to cover a portion of the polysilicon layer within the first cavity;
• depositing a bonding material on a portion of polysilicon layer within the first, the second, and the third standoff regions;
• depositing another mask over the polysilicon layer, the bonding material, and the getter material;
• patterning the another mask to expose a portion of the polysilicon layer within the first cavity and wherein the patterned another mask covers the patterned getter material within the first cavity;
• and
• etching regions of the polysilicon layer and the substrate that are exposed by the patterned another mask within the first cavity to form a first and a second cavity regions within the first cavity.

A method comprising:

• depositing an intermetal dielectric (IMD) layer over a substrate;
• forming a first mask over the IMD layer;
• patterning the first mask to form a patterned first mask, wherein a first exposed portion of the patterned first mask is associated with a first cavity region positioned between a first and a second standoff regions and a second exposed portion of the patterned mask is associated with a second cavity region positioned between the second and a third standoff regions, and wherein the patterned first mask covers the first, the second, and the third standoff regions;
• etching exposed portions of the IMD layer based on the patterned first mask to form a first cavity within the first cavity region and a second cavity within the second cavity region and further to form a first, a second, and a third standoff associated with the first, the second, and the third standoff regions respectively;
• forming a second mask over the patterned first mask and further over exposed portions of the IMD layer;
• patterning the second mask to form a patterned second mask, wherein the patterned second mask covers a region associated with a first bumpstop within the first cavity and a region associated with a second bumpstop within the second cavity, and wherein the patterned second mask further covers the first, the second, and the third standoff regions;
• etching exposed portions of the IMD based on the patterned second mask to form the first bumpstop and the second bumpstop;
• removing the patterned second mask;
• depositing a polysilicon layer over the patterned first mask and further in the first cavity and the second cavity and the first and the second bumpstops;
• forming a getter material over the polysilicon layer;
• patterning the getter material to cover a portion of the polysilicon layer within the first cavity;
• patterning the polysilicon layer that is exposed, wherein patterning the polysilicon layer exposes a portion of the IMD layer within the first cavity and the second cavity while covering the first and the second bumpstops;
• and
• forming a bonding material over the polysilicon layer on the first, the second, and the third standoffs.

A method comprising:

• depositing a first intermetal dielectric (IMD) layer over a substrate;
• forming a first mask over the first IMD layer;
• patterning the first mask to form a patterned first mask to cover a region of the first IMD layer associated with a first bumpstop within a first cavity region and to cover a region of the first IMD layer associated with a second bumpstop within a second cavity region;
• etching exposed portions of the first IMD layer based on the patterned first mask to form the first bumpstop and the second bumpstop;
• forming a polysilicon layer over the first IMD layer, the first bumpstop, and the second bumpstop;
• forming a getter material over the polysilicon layer;
• patterning the getter material to cover a portion of the polysilicon layer within the first cavity region;
• forming a second mask over the polysilicon layer and the patterned getter material;
• patterning the second mask to form a patterned second mask;
• etching exposed portions of the polysilicon layer to expose the first IMD layer underneath;
• depositing a second IMD layer over the exposed first IMD layer and further over the polysilicon layer;
• forming a passivation layer over the second IMD layer;
• forming a first, a second, and a third via in a first, a second, and a third standoff regions respectively by etching through the passivation layer and the second IMD layer and to reach the polysilicon layer, wherein the first cavity region is between the first and the second standoff regions and wherein the second region is between the second and the third standoff region;
• filling the first, the second, and the third vias;
• forming a bonding material over the first, the second, and the third vias;
• forming a third mask over the first, the second, and the third standoff regions;
• etching the passivation layer over the second IMD layer within the first cavity region and the second cavity region based on the third mask that exposes the polysilicon layer underneath the second IMD layer and further that exposes a portion of the first IMD layer and that forms a first cavity associated with the first cavity region and a second cavity associated with the second cavity region;
• and
• removing the third mask to expose the bonding material.