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Design complexity and space constraints are pushing designers to innovative novel solutions. Placing a die inside a cavity is the most common and effective technique and you have most probably used it if you are designing an application for the automotive industry or the Microwave/Telecommunications domain. Allegro® Package Designer Plus provides a complete range of toolset right from setting the design in the cavity to cavity-specific DRC checks to manufacturing. In this blog, we will discuss the steps to wire bond a design for an open stadium cavity style.
We will explain in detail the following design-flow steps for the wire bond stadium cavity:
Placing the die inside a cavity is an easy task using Die-stack Editor:
Applying these changes creates the stadium cavity automatically in the design. It also creates the Route keepout on the layers where the cavity is created, and the Component keepout on the Top substrate layer.
The following image shows die placement in a cavity. The stadium cavity is created per the clearance and expansion values. The Report in the Die-stack Editor is also updated to show the cavity-related changes.
To start wire bonding, first define the bond fingers in the cavity:
Multiple assembly rules are available for wire bond-specific cavity designs. To select and apply these rules, open Assembly Design Rules Checks dialog from Manufacture – Assembly Rules Checker. Enable the Bond Fingers to Cavity Spacing constraint under the Cavity category and click OK.
The batch DRC process runs and generates a report. You can see DRC markers in the design for any violation against those checks. Use the show element command and select a marker to view the constraint violation details.
There are more Assembly checks for the cavity-specific wire bond designs. These checks are available under the Wire Spacing Assembly rule selection.
3D Viewer supports cavity design. Run View ─ 3D Model to launch the Cadence 3D viewer. By setting up the 3D DRCs rules, you can verify DRCs in a design. The next image shows a die in the cavity with bond fingers on multiple layers.
Allegro Package Designer Plus provides a comprehensive set of functionalities to successfully create a design package with a cavity. I encourage you to design your next wire bond cavity package using this powerful set of functionalities. Do SUBSCRIBE to stay updated about upcoming blogs. If there is any topic you want us to cover or any feedback to share, write to us at firstname.lastname@example.org.