A method includes forming a bumpstop from a first intermetal dielectric (IMD) layer and forming a via within the first IMD, wherein the first IMD is disposed over a first polysilicon layer, and wherein the first polysilicon layer is disposed over another IMD layer that is disposed over a substrate. The method further includes depositing a second polysilicon layer over the bumpstop and further over the via to connect to the first polysilicon layer. A standoff is formed over a first portion of the second polysilicon layer, and wherein a second portion of the second polysilicon layer is exposed. The method includes depositing a bond layer over the standoff.

A device includes a substrate and an intermetal dielectric (IMD) layer disposed over the substrate. The device also includes a first plurality of polysilicon layers disposed over the IMD layer and over a bumpstop. The device also includes a second plurality of polysilicon layers disposed within the IMD layer. The device includes a patterned actuator layer with a first side and a second side, wherein the first side of the patterned actuator layer is lined with a polysilicon layer, and wherein the first side of the patterned actuator layer faces the bumpstop. The device further includes a standoff formed over the IMD layer, a via through the standoff making electrical contact with the polysilicon layer of the actuator and a portion of the second plurality of polysilicon layers and a bond material disposed on the second side of the patterned actuator layer.

Provided herein is a method including fusion bonding a handle wafer to a first side of a device wafer. Standoffs are formed on a second side of the device wafer. A first hardmask is deposited on the second side. A second hardmask is deposited on the first hardmask. A surface of the second hardmask is planarized. A photoresist is deposited on the second hardmask, wherein the photoresist includes a MEMS device pattern. The MEMS device pattern is etched into the second hardmask. The MEMS device pattern is etched into the first hardmask, wherein the etching stops before reaching the device wafer. The photoresist and the second hardmask are removed. The MEMS device pattern is further etched into the first hardmask, wherein the further etching reaches the device wafer. The MEMS device pattern is etched into the device wafer. The first hardmask is removed.

A forming method of a thin layer with a pore is provided. The method includes forming a thin layer on a substrate, stacking a first mask and a second mask on the thin layer in this order, and forming a pore in the thin layer by dry etching. The first mask includes at least a self-assembling material. The second mask is more resistant to reactive etching or physical etching than the first mask.

A method of etching features in a silicon wafer includes coating a top surface and a bottom surface of the silicon wafer with a mask layer having a lower etch rate than an etch rate of the silicon wafer, removing one or more portions of the mask layer to form a mask pattern in the mask layer on the top surface and the bottom surface of the silicon wafer, etching one or more top surface features into the top surface of the silicon wafer through the mask pattern to a depth plane located between the top surface and the bottom surface of the silicon wafer at a depth from the top surface, coating the top surface and the one or more top surface features with a metallic coating, and etching one or more bottom surface features into the bottom surface of the silicon wafer through the mask pattern to the target depth plane.

Provided herein is a method including fusion bonding a handle wafer to a first side of a device wafer. A hardmask is deposited on a second side of the device wafer, wherein the second side is planar. The hardmask is etched to form a MEMS device pattern and a standoff pattern. Standoffs are formed on the device wafer, wherein the standoffs are defined by the standoff pattern. A eutectic bond metal is deposited on the standoffs, the device wafer, and the hardmask. A first photoresist is deposited and removed, such that the first photoresist covers the standoffs. The eutectic bond metal is etched using the first photoresist. The MEMS device pattern is etched into the device wafer. The first photoresist and the hardmask are removed.

The present invention relates to a free-standing single crystalline diamond part and a single crystalline diamond part production method. The method includes the steps of: providing a single crystalline diamond substrate or layer; providing a first adhesion layer on the substrate or layer; providing a second adhesion layer on the first adhesion layer: providing a mask layer on the second adhesion layer; forming at least one indentation or a plurality of indentations through the mask layer and the first and second adhesion layers to expose a portion or portions of the single crystalline diamond substrate or layer; and etching the exposed portion or portions of the single crystalline diamond substrate or layer and etching entirely through the single crystalline diamond substrate or layer.

A process for fabricating a symmetrical MEMS accelerometer. A pair of half parts is fabricated by, for each half part: (i) forming a plurality of resilient beams, first connecting parts, second connecting parts, and a plurality of comb structures, by etching a plurality of holes on a bottom surface of a first silicon wafer; (ii) etching a plurality of hollowed parts on a top surface of a second silicon wafer; (iii) forming a silicon dioxide layer on the top and bottom surface of the second silicon wafer; (iv) bonding the bottom surface of the first silicon wafer with the top surface of the second silicon wafer; (v) depositing a layer of silicon nitride on the bottom surface of the second silicon wafer, and removing parts of the silicon nitride layer and silicon dioxide layer on the bottom surface of the second silicon wafer; (vii) deep etching the exposed parts of the bottom surface of the second silicon wafer to the silicon dioxide layer located on the top surface of the second silicon wafer, and reducing the thickness of the first silicon wafer; and (viii) removing the silicon nitride layer, and etching the silicon dioxide to form the mass. The two half parts are then bonded along their bottom surface. The device is deep etched to form a movable accelerometer. A bottom cap is fabricated by hollowing out the corresponding area, and depositing metal as electrodes. The accelerometer is bonded with the bottom cap. Metal is deposited on the first silicon wafer to form electrodes.

Provided herein is a method including fusion bonding a handle wafer to a first side of a device wafer. A hardmask is deposited on a second side of the device wafer, wherein the second side is planar. The hardmask is etched to form a MEMS device pattern and a standoff pattern. Standoffs are formed on the device wafer, wherein the standoffs are defined by the standoff pattern. A eutectic bond metal is deposited on the standoffs, the device wafer, and the hardmask. A first photoresist is deposited and removed, such that the first photoresist covers the standoffs. The eutectic bond metal is etched using the first photoresist. The MEMS device pattern is etched into the device wafer. The first photoresist and the hardmask are removed.

Provided herein is a method including fusion bonding a handle wafer to a first side of a device wafer. Standoffs are formed on a second side of the device wafer. A first hardmask is deposited on the second side. A second hardmask is deposited on the first hardmask. A surface of the second hardmask is planarized. A photoresist is deposited on the second hardmask, wherein the photoresist includes a MEMS device pattern. The MEMS device pattern is etched into the second hardmask. The MEMS device pattern is etched into the first hardmask, wherein the etching stops before reaching the device wafer. The photoresist and the second hardmask are removed. The MEMS device pattern is further etched into the first hardmask, wherein the further etching reaches the device wafer. The MEMS device pattern is etched into the device wafer. The first hardmask is removed.