Electrode structure and method for anodically-bonded capacitive sensors
AssigneeLitton Systems, Inc.
InventorKeith O. Warren
Life of this patent
Estimating the term…
Abstract
A sensing electrode on a glass layer of an anodically-bonded capacitive sensor has an interfacial barrier film containing a nitride compound between the electrode and the glass layer. In one embodiment, the capacitive sensor is an inertial sensor having a sensing element hingedly mounted to a frame which is anodically bonded to the glass layer. The sensing electrode is then located on a surface of the glass layer facing the sensing element. The sensing element and the frame are preferably made of silicon and the interfacial film is preferably silicon nitride.
Claims22
An anodically-bonded capacitive sensor comprising:
- a sensing element having a frame structure;
- at least one glass layer anodically bonded to the frame structure and having a metallic sensing electrode adjacent the sensing element;
- and
- a patterned interfacial barrier layer on the glass layer, said pattered interfacial barrier layer disposed between the glass layer and the metallic sensing electrode.
An anodically-bonded capacitive sensor comprising:
- a substantially planar sensing element and frame structure made up of a semiconductor material;
- a pair of glass layers anodically bonded to oppositely-directed surfaces of the frame structure, each of said glass layers having a metallic sensing electrode spatially opposed to the sensing element;
- and
- a patterned interfacial barrier layer containing a nitride compound on each of the glass layers, each of said one of the glass layers and its metallic sensing electrode.
An anodically-bonded inertial sensor comprising:
- a substantially planar proof mass hingedly connected to a frame structure, the proof mass and the frame structure comprising a monolithic silicon body;
- a pair of glass layers anodically bonded to oppositely-directed surfaces of the frame structure, each of said glass layers having a metallic sensing electrode spatially opposed to the proof mass;
- and
- a patterned interfacial nitride film on each of the glass layers, each of said patterned interfacial nitride films being disposed between one of the glass layers and its metallic sensing electrode.
A method of manufacturing a capacitive sensor comprising the steps of:
- providing a sensing element connected to a frame structure;
- providing at least one glass sheet having a preselected area corresponding to the sensing element;
- forming a patterned barrier layer on the preselected area of the glass sheet;
- depositing a metallic sensing electrode on said patterned barrier layer;
- and
- anodically bonding the glass layer to the frame structure so that the metallic sensing electrode spatially opposes the sensing element.
A method of manufacturing an inertial sensor comprising the steps of:
- providing a proof mass connected to a frame structure;
- providing at least one glass sheet having a preselected area corresponding to the proof mass;
- forming a patterned nitride layer on the preselected area of the glass sheet;
- depositing a metallic sensing electrode on said patterned nitride layer;
- and
- anodically bonding the glass layer to the frame structure so that the metallic sensing electrode spatially opposes the proof mass.
Dependencies are inferred from the claim text.