Silicon Light Machines Corporation

Cypress Semiconductor Corporation

Mike Bruner

Gregory David Miller

Krishnaswamy Ramkumar

James A Hunter

Mira Ben-Tzur

Thurman John Rodgers

Lawrence Ragan

Gary W Green

Jim Hunter

Richard Yeh

Klyoko Keuchi

Klyoko Ikeuchi

One embodiment disclosed relates to a method for sealing an active area of a non-silicon-based device on a wafer. The method includes providing a sacrificial material over at least the active area of the non-silicon-based device, depositing a seal coating over the wafer so that the seal coating covers the sacrificial material, and replacing the sacrificial material with a target atmosphere. Another embodiment disclosed relates to a non-silicon-based device sealed at the wafer level (i.e. prior to separation of the die from the wafer). The device includes an active area to be protected, a contact area, and a lithographically-formed structure sealing at least the active area and leaving at least a portion of the contact area exposed.

Wafer-level seal for non-silicon-based devices

In one embodiment, a sacrificial layer is deposited over a base layer. The sacrificial layer is used to define a subsequently formed floating metal structure. The floating metal structure may be anchored into the base layer. Once the floating metal structure is formed, the sacrificial layer surrounding the floating metal structure is etched to create a unity-k dielectric region separating the floating metal structure from the base layer. The unity-k dielectric region also separates the floating metal structure from another floating metal structure. In one embodiment, a noble gas fluoride such as xenon difluoride is used to etch a sacrificial layer of polycrystalline silicon.

Method of forming a floating metal structure in an integrated circuit

The current invention provides for encapsulated release structures, intermediates thereof and methods for their fabrication. The multi-layer structure has a capping layer, that preferably comprises silicon oxide and/or silicon nitride, and which is formed over an etch resistant substrate. A patterned device layer, preferably comprising silicon nitride, is embedded in a sacrificial material, preferably comprising polysilicon, and is disposed between the etch resistant substrate and the capping layer. Access trenches or holes are formed in to capping layer and the sacrificial material are selectively etched through the access trenches, such that portions of the device layer are release from sacrificial material. The etchant preferably comprises a noble gas fluoride NGF(wherein Ng=Xe, Kr or Ar: and where x=1, 2 or 3). After etching that sacrificial material, the access trenches are sealed to encapsulate released portions the device layer between the etch resistant substrate and the capping layer. The current invention is particularly useful for fabricating MEMS devices, multiple cavity devices and devices with multiple release features.

Microelectronic mechanical system and methods

The current invention provides for encapsulated release structures, intermediates thereof and methods for their fabrication. A multi-layer structure has a capping layer, that preferably comprises silicon oxide and/or silicon nitride, and which is formed over an etch resistant substrate. A patterned device layer, preferably comprising silicon nitride, is embedded in a sacrificial material, preferably comprising poly-silicon, and is disposed between the etch resistant substrate and the capping layer. Access trenches or holes are formed in to capping layer and the sacrificial material is selectively etched through the access trenches, such that portions of the device layer are release from sacrificial material. The etchant preferably comprises a noble gas fluoride NGF, (wherein NG=Xe, Kr or Ar: and where x=1, 2 or 3). After etching that sacrificial material, the access trenches are sealed to encapsulate released portions the device layer between the etch resistant substrate and the capping layer. The current invention is particularly useful for fabricating MEMS devices, multiple cavity devices and devices with multiple release features.

One embodiment disclosed relates to a method for sealing an active area of a surface acoustic wave (SAW) device on a wafer. The method includes providing a sacrificial material over at least the active area of the SAW device, depositing a seal coating over the wafer so that the seal coating covers the sacrificial material, and replacing the sacrificial material with a target atmosphere. Another embodiment disclosed relates to an SAW device sealed at the wafer level (i.e. prior to separation of the die from the wafer). The device includes an active area to be protected, an electrical contact area, and a lithographically-formed structure sealing at least the active area and leaving at least a portion of the electrical contact area exposed.

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Saratoga, CA, United States of America

Mike Bruner