IC Packagers: 17.4-2019 Hotfix 019 Is Here! What Does That Mean?

The HotFix 019 of our 17.4-2019 release is available for download and installation, now. This marks our third major update of this release stream, and that means a host of bug fixes, enhancements, and new features. I’m excited to get to talk about them with you, finally! Sit back and relax; let’s go through the biggest items that are going to improve your package design experience with Allegro^® Package Designer Plus.

Layer-Based Degassing 

Of everything that you’ll find in this update, this excites me the most. Degassing is a core tool for nearly all package designs today, whether you’re working on a traditional laminate substrate or a more advanced node manufactured in silicon.

Earlier in 17.4-2019, we introduced you to advanced degassing under the Silicon Layout option license and menu, which provided up to a 50x performance improvement over traditional degassing while shrinking the database size significantly.

Hotfix 019 takes this a step further. First, you will need to enable layer-based degassing by adding the DEGAS_LAYER_BASED_ENABLED design level property. As the new capabilities require a database schema update, this property ensures you can still work in compatibility mode if you’re not yet ready to make use of the layer-based parameters.

Once this has been added, open the global shape parameters dialog and you’ll see a new tab. Here, you can define all the different degassing patterns that you will use in your design and assign patterns (or sets of patterns) to each layer in your design. See the basic UI, below:

You can add, redefine, or just view all the patterns here in the UI. Then, you can assign specific patterns to each layer in the lower section of the form. By defining the degassing here in the shape parameters form, you’ll get many benefits, including:

• The ability to add, remove, or modify individual patterns without redefining all others,

• Parameters will automatically apply to new shapes you add on layers without you having to do anything beyond updating the degassing hole pattern on them,

• Visually seeing the relationship of patterns between layers. Since it is not ideal to overlap holes on one layer with those on its neighbors, you can immediately see this and correct it where needed.

Should you need to have special parameters on a specific shape, you have not lost this ability. Rather, you can customize parameters for that shape the same way you would customize thermal ties, voiding style, or oversize clearance parameters. From the shape edit application mode, RMB on the shape and pick Parameters from the menu. Here, you will see the values assigned to the shape by the layer and can further refine the configuration.

Hopefully, you will find you need to go into the standalone degassing tool (whether the traditional Manufacturing menu command or the SI Layout menu’s advanced degassing) far less frequently. The less time you spend configuring patterns, the more time there is for design work!

Acute Angle Cover Improvements 

The acute angle cover tool has proven to be a huge time saver for many of you. With the HotFix19 update, therefore, we have listened to your feedback on how to make it even better! Below, you’ll see the previous interface side-by-side with the new.

Notice that the previous minimum corner distance global setting has been removed, as has the arc corners option. These have been relocated to the layer grid parameters, allowing you to configure values and styles on a per-layer basis – much like the layer-based degassing.

This is not the most significant change, however. Instead of a corner distance, the tool now asks you for a minimum length for the chamfer/arc. This is the length of the segment that removes the acute angle. As shown below, this value is more directly tied to your manufacturing design constraints.

As the angle of intersection becomes sharper, the correcting shape becomes longer, automatically ensuring that you don’t swap acute angle and acid trap concerns for minimum segment length problems.

You’ll still find the same tight integration with the acute angle assembly rule check DRC tool and the ability to control the shape’s object type when performing DRC spacing checks and dynamic voiding.

Stream vs Layout Comparison 

Our third and final item for this, our first look at HotFix 019, is the new GDSII Verification tool. The GUI is shown below:

As the stream format does not have support for arcs, there will be some element of conversion that happens during any export to this manufacturing format from your layout database. How, then, do you ensure that the *only* differences between the GDS data you are sending to manufacturing and the layout itself are the result of the vectorization of arcs?

Enter this exciting new tool, available under the SI Layout menu. When run and provided with the GDS file you intend to send for manufacturing (and the conversion file you used to generate it), the tool can analyze the differences between the two data sources, accounting for arc vectorization, mirroring, and rotation of the output.

After running, you receive a concise report detailing the number of differences resulting from arc vectorization and, in the event of any other differences (while unlikely), the location and size/shape of the difference. You may then check these differences using the Layer Compare tool’s Difference Walker.

If the results are acceptable to you – they may be intentional due to your conversion file’s map, for instance – then you are safe to send your data to your manufacturing partner. Otherwise, you can make changes to your design or, should the problem be with the exported GDS itself, contact Cadence^® for immediate resolution.

This is Just the Beginning… 

While exciting, these are just the first of many updates available to you in HotFix 019. Come back next week to learn about even more tools that will see you complete your designs in record time using Allegro Package Designer Plus. And, as ever, thank you for helping us make the tool the absolute best it can be for our worldwide community!

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