Techniques for curvature control in power transistor devices
AssigneeAgere Systems Inc.
InventorsRoger A. Fratti, Warren K. Waskiewicz
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Abstract
Techniques for processing power transistor devices are provided. In one aspect, the curvature of a power transistor device comprising a device film formed on a substrate is controlled by thinning the substrate, the device having an overall residual stress attributable at least in part to the thinning step, and applying a stress compensation layer to a surface of the device film, the stress compensation layer having a tensile stress sufficient to counterbalance at least a portion of the overall residual stress of the device. The resultant power transistor device may be part of an integrated circuit.
Claims16
A method for controlling curvature of a power transistor device comprising a device film formed on a substrate, the method comprising the steps of:
- thinning the substrate, the device having an overall residual stress attributable at least in part to the thinning step;
- and
- applying a stress compensation layer to a surface of the device film, the stress compensation layer having a tensile stress sufficient to counterbalance at least a portion of the overall residual stress of the device and to configure a curvature of the device to be between flat and slightly convex.
A power transistor device comprising:
- a substrate;
- and
- a device film formed on the substrate, the device having an overall residual stress attributable at least in part to a thinning process applied to the substrate;
- wherein the power transistor device further comprises a stress compensation layer formed on a surface of the device film, the stress compensation layer having a tensile stress that counterbalances at least a portion of the overall residual stress of the device.
An integrated circuit, comprising:
- at least one power transistor device comprising a substrate and a device film formed on the substrate, the device having an overall residual stress attributable at least in part to a thinning process applied to the substrate;
- wherein the power transistor device further comprises a stress compensation layer formed on a surface of the device film, the stress compensation layer having a tensile stress that counterbalances at least a portion of the overall residual stress of the device.
Dependencies are inferred from the claim text.