A method includes forming a first mask on a first portion of a first surface of a substrate, forming a second mask on the first mask and further forming the second mask on a second portion of the first surface of the substrate, and etching an exposed portion of the first surface of the substrate and removing the second mask. According to some embodiments, an exposed portion of the first surface of the substrate is etched and the first mask is removed. An oxide layer is formed on the first surface of the substrate. A third mask is formed on the oxide layer except for a portion of the oxide layer corresponding to bumpstop features. The portion of the oxide layer corresponding to the bumpstop features is removed. An exposed portion of the first surface of the substrate is etched and the third mask is removed.

A method includes forming a first mask on a first portion of a first surface of a substrate, forming a second mask on the first mask and further forming the second mask on a second portion of the first surface of the substrate, and etching an exposed portion of the first surface of the substrate and removing the second mask. According to some embodiments, an exposed portion of the first surface of the substrate is etched and the first mask is removed. An oxide layer is formed on the first surface of the substrate. A third mask is formed on the oxide layer except for a portion of the oxide layer corresponding to bumpstop features. The portion of the oxide layer corresponding to the bumpstop features is removed. An exposed portion of the first surface of the substrate is etched and the third mask is 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.

A MEMS device and a method of forming the same. A disclosed method includes: providing a silicon substrate layer, a buried oxide layer and a device silicon layer; using a microfabrication process to pattern a set of device features on the device silicon layer including a shuttle mass and an anchor frame; removing the silicon substrate layer and buried oxide below the shuttle mass; placing a shadow mask on a surface of the device silicon layer, wherein the shadow mask has an microscale opening to expose at least one device feature; and forming a nanoscale stopper on a sidewall of the at least one device feature by depositing a deposition material through the opening in a controlled manner.

A method for forming a functionalised assembly guide intended for the self-assembly of a block copolymer by graphoepitaxy, includes forming on the surface of a substrate a neutralisation layer made of a first material having a first neutral chemical affinity with regard to the block copolymer; forming on the neutralisation layer a first mask including at least one recess; depositing on the neutralisation layer a second material having a second preferential chemical affinity for one of the copolymer blocks, in such a way as to fill the at least one recess of the first mask; and selectively etching the first mask relative to the first and second materials, thereby forming at least one guide pattern made of the second material arranged on the neutralisation layer.

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.

An embodiment as described herein includes a microelectromechanical system (MEMS) with a first MEMS transducer element, a second MEMS transducer element, and a semiconductor substrate. The first and second MEMS transducer elements are disposed at a top surface of the semiconductor substrate and the semiconductor substrate includes a shared cavity acoustically coupled to the first and second MEMS transducer elements.

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.

An embodiment as described herein includes a microelectromechanical system (MEMS) with a first MEMS transducer element, a second MEMS transducer element, and a semiconductor substrate. The first and second MEMS transducer elements are disposed at a top surface of the semiconductor substrate and the semiconductor substrate includes a shared cavity acoustically coupled to the first and second MEMS transducer elements.