The disclosure relates to a method for manufacturing recessed micromechanical structures in a MEMS device wafer. First vertical trenches in the device wafer define the horizontal dimensions of both level and recessed structures. The horizontal face of the device wafer and the vertical sidewalls of the first vertical trenches are then covered with a self-supporting etching mask which is made of a self-supporting mask material, which is sufficiently rigid to remain standing vertically in the location where it was deposited even as the sidewall upon which it was deposited is etched away. Recess trenches are then etched under the protection of the self-supporting mask. The method allows a spike-preventing aggressive etch to be used for forming the recess trenches, without harming the sidewalls in the first vertical trenches.

In an embodiment, a method for manufacturing a micro-electro-mechanical systems (MEMS) transducer device includes providing a substrate body with a surface, depositing an etch-stop layer (ESL) on the surface, depositing a sacrificial layer on the ESL, depositing a diaphragm layer on the sacrificial layer and removing the sacrificial layer, wherein depositing the sacrificial layer includes depositing a first sub-layer of a first material and depositing a second sub-layer of a second material, and wherein the first material and the second material are different materials.

In an embodiment, an integrated MEMS transducer device includes a substrate body having a first electrode on a substrate, an etch stop layer located on a surface of the substrate, a suspended micro-electro-mechanical systems (MEMS) diaphragm with a second electrode, an anchor structure with anchors connecting the MEMS diaphragm to the substrate body and a sacrificial layer in between the anchors of the anchor structure, the sacrificial layer including a first sub-layer of a first material, wherein the first sub-layer is arranged on the etch stop layer, a second sub-layer of a second material, wherein the second sub-layer is arranged on the first sub-layer, and wherein the first and the second material are different materials.

Embodiments of the disclosure provide methods for microfabricating an omni-view peripheral scanning system. One exemplary method may include separately fabricating a reflector and a scanning MEMS mirror, and then bonding the microfabricated reflector with the scanning MEMS mirror to form the omni-view peripheral scanning system. The microfabricated reflector may include a cone-shaped bottom portion, and a via hole across the cone-shaped bottom portion. The microfabricated scanning MEMS mirror may include a MEMS actuation platform and a scanning mirror supported by the MEMS actuation platform. The scanning MEMS mirror may face the cone-shaped bottom portion of the reflector when forming the omni-view peripheral scanning system.

A structure forming method according to an aspect is a structure forming method for forming a first hole and a second hole having width smaller than width of the first hole in a substrate with dry etching and forming a structure. The structure forming method includes forming an etching mask on the substrate, etching a portion of the etching mask overlapping a first hole forming region where the first hole is formed, etching a portion of the etching mask overlapping a second hole forming region where the second hole is formed, and performing the dry etching of the substrate using the etching mask as a mask.

A method of manufacturing a semiconductor substrate according to an embodiment includes a first step of forming a groove having a bottom surface and a side surface on which scallops are formed by performing a process including isotropic etching on a main surface of a substrate, a second step of performing at least one of a hydrophilic treatment on the side surface of the groove and a degassing treatment on the groove, and a third step of removing the scallops formed on the side surface of the groove and planarizing the side surface by performing anisotropic wet etching in a state where the bottom surface of the recess is present.

A method of processing an object using a plasma processing apparatus is provided. The plasma processing apparatus includes a stage on which the object is placed in a chamber, an outer peripheral member disposed around the stage, a first power supply configured to apply voltage to the outer peripheral member, and a memory storing information about a relationship between the voltage applied to the outer peripheral member and an adjustment amount of a process parameter. The method includes: applying voltage from the first power supply to the outer peripheral member; adjusting the process parameter based on the voltage applied to the outer peripheral member, by referring to the information stored in the memory; and performing a plasma process under a process condition including the adjusted process parameter.

In an embodiment, a method for manufacturing a micro-electro-mechanical systems (MEMS) transducer device includes providing a substrate body with a surface, depositing an etch-stop layer (ESL) on the surface, depositing a sacrificial layer on the ESL, depositing a diaphragm layer on the sacrificial layer and removing the sacrificial layer, wherein depositing the sacrificial layer includes depositing a first sub-layer of a first material and depositing a second sub-layer of a second material, and wherein the first material and the second material are different materials.

In one example, a method comprises forming a first layer on a substrate surface, forming an opening in the first layer, forming a second layer on the first layer and in the opening, and forming a photoresist layer on the second layer, in which the photoresist layer has a first curved surface over a first part of the first layer and over the opening. The method further comprises etching the photoresist layer and a second part of the second layer over the first part of the first layer to form a second curved surface on the second part of the second layer, and forming a mirror element and a support structure in the second layer, including by etching a third part of the second layer and removing the first layer.

Described examples include an apparatus having a substrate with a substrate surface. The apparatus also includes an element with a planar surface facing the substrate surface and with a nonplanar surface opposite the planar surface facing away from the substrate surface.