Overview of 3D CAD design tools

In this chapter we will show and explain the current status of commercial available tools which are needed to bring a 3D system from the idea to a manufactured system. Depending on the design complexity, existing 2D tools can directly be used to design parts of the 3D system. In some cases add-ons for the 2D tools are required and for complex designs new tools are needed. Similar to the 2D case, a 3D design flow can be divided into a construction phase and a corresponding verification phase. If we look at these two phases then we can divide both into two major sections - a 3D and a 2D section. If the design reaches the 2D section the 3D system is broken into classical 2D (sub-) systems (chips, interposers) and corresponding system integration elements between them (e.g., balls). Thus, the goal of the 3D design is to structure the 3D system into 2D (sub-) systems and some connecting elements. Tools which divide the 3D system into the 2D systems must consider different requirements such as timing, temperature, and fabrication costs. System-level design exploration should take place at a very early design stage. Most of the required interaction should be done within the 3D design space. On the other hand, to get a detailed evaluation of a chosen design option, the 2D tools can be involved as well. But this kind of interaction should be limited to a minimum as it is often time consuming. For verification, we separate into 2D and 3D as well. In the 2D section the classical 2D system verification steps take place, such as Design Rule Check (DRC), Layout versus Schematic (LVS), parasitic extraction, timing verification, optical proximity correction (OPC).