GemPackage can accept 3D information and visualize the design in 3D. It accepts 3D information such as bonding wire profiles, thickness of chips, thicknesses of substrate layers (including conductor layers, dielectric layers, adhesive layers, resist layers, etc), dimensions of solder balls and microbump balls, package mold height, etc. Once the 3D information is set, GemPackage's canvas can be turned into "Quasi-3D" style, which shows the design from a slightly angled position, as in the figure. The angle is adjustable accordingly. It is called "quasi-3D" because it is a set of 2D images, stacked for each layer with offsets. The mouse operation on the canvas such as selecting objects or moving objects are constrained in 2D planes. This limitation keeps the operation easier then real 3D style, while the stacked objects can be differentiated easier than the traditional 2D canvas.

  In the design review meetings in the FS phase, it is very important for the members to share global physical image of their target SiP. Realistic 3D observation is more suited for such occasions. For such purposes, Google tools are suited.

  GemPackage can export data to Google Earth. With the intuitive user interface in Google Earth, you can easily observe the 3D model from various angles. (above figure).

  The 3D model data of Google Earth is nicely organized by GemPackage. For example, pattern and vias can be displayed net by net, layer by layer, as well as for selected nets in highlighted colors. This feature is useful to discuss the goodness of the net assignment plan. Bonding wire dimension information can be shown from the assembly engineer's perspective; minimum wire gap, gap to chip corner, minimum room to the ceiling of the package mold, or to the bottom of the hanging over chip, etc.

  Sample data file for Google Earth can be downloaded here (pop.kmz, 200KB). To display the model, start Google Earth, and then open the file by File/Open menu. Soon you will see a huge PoP model placed on an airport. On the left side of the screen, there is 'Place' column, where you can turn on/off the visibility of the data items. It is a good idea to use "SpaceNavigator" (see reference) since it enables intuitive pose control in 3D space.

  GemPackage can also export 3d model for Google SketchUp, via ruby script file. Using SketchUp, you can examine your model more in detail (above figure), measure dimensions at arbitrary positions, and create other 3D objects such as heatsinks.

  Sample file can be downloaded here (pop.rb, 900KB). To read the file in SketchUp, click 'Window' menu, select 'Ruby console' in the menu. The 'ruby console' appears, where you can enter the command like 'load "C:/xxx/xxx/pop.rb"'. Wait for 'completed' message for a while, close the console, set the unit to 'inch' using 'Window/Model Info/Units'. Major appearance can be controlled in 'Window/Styles'. Visible items can be set up using 'Window/Layers'. Once you have finished such settings, you can store the result in 'skp' format file, to speed up opening next time. The resultant skp file can be downloaded here (pop.skp, 4.4MB). To open skp file on SketchUp, simply use "File/Open" menu. SpaceNavigator works fine on SketchUp too.

Advancement in packaging technology has enabled more and more objects stacked vertically, and will enhance this direction further in the future. GemPackage supports not only the chip stacking, but also tomorrow's technologies such as embedded substrate and TSV-based 3D-ICs. (See Advanced Packages for details.)