Metal Elbows with Lithography Models : Metal Elbows with Lithography Models

Requires: CLEVER

CLEVER is used in this example to simulate an "L" shaped metal region, often found in custom cells, which is insulated from the silicon substrate by a 0.5um oxide layer. The processing steps are very simple requiring only etching and deposition.

As with any CLEVER simulation the process etching steps are driven from a layout file generated from MaskViews. This file will be included in the support files when this example is loaded.

A more physical etch model is applied, compared with the previous example, where optical lithography is used. Now the wavelength of light is defined with the Illumination statement and optical lithography enabled with the Litho parameter of the Mask statement. This simulates the deposition of resist and its imaging through the mask. The resultant resist shape therefore becomes much more physical so that when the subsequent etch is performed a much more realistic metal shape is produced compared to Example 1. The etching model in this example is the same as in Example

Once the process simulation is complete the three-dimensional structure is saved with the Save statement and can be plotted using TonyPlot3d.

Finally the interconnect parasitic extraction is carried out using the Interconnect statement. Firstly, however, the material parameters of silicon are defined using the Material statement so that in this case silicon "inherits" the same material properties as silicon. In this example only the parasitic capacitance values are calculated from the field solver. During this calculation automatic mesh adaption is performed with the Adapt parameter whereby the mesh is modified until the error in the capacitance extraction is reduced to the default maximum of 5% of the capacitance. The structure and the spice netlist are then saved.

To load and run this example, select the Load example button in DeckBuild. This will copy the input file and any support files to your current working directory. Select the run button to execute the example.