orientation of metal layers

[argha]

plz explain me the about the metal layers how they are arranged i.e vertical as well as horizontal layers with power rings,stripes and rails.


thank you in advance....

:smile::smile:

 

[vikramrajput]

Hi,

as we know there are two types of routing tech we follow while designing the chip. 1) Global routing. 2) Detailed routing.

The goal of the global routing is to route as many nets as possible while meeting the capacity constraints of each edge and any other constraints if possible.

While in detailed routing , we decides actual physical interconnections of nets by allocating wire on each metal layers and vias for switching between metal layers.

Generally, there are two different layer models, the reserved and unreserved layer models. In the reserved layer model, each layer is allowed only one specific routing direction (i.e., preferred direction). For example, the technology file may specify that the wires in the first metal layer are allowed to run only in the horizontal direction, the second metal layer contains only vertical wires, etc. A layer model is unreserved if it allows the placement of wires with any directions (i.e.,
non-preferred direction). Most of the existing routers and design methodologies apply the reserved layer model, because it has lower complexity than the unreserved layer model and is much easier for implementation.

I hope you have got some info from this.