M1 PG nets problem in Astro

[eexuke]

Dear experts,
When I am using Astro, I met a strange problem:
1) Consider total height of my std cell's height = 5 (1 VDD,1VSS and 3 for remaining) and both VDD and VSS are consisted of M1.
2) When I create M1 PG nets for all standard cells, the distance between the center of two adjacent PG nets is 4 (I use double back and distance=4 is just what I desired).
3) However,the width of each PG nets become 2 instead of 1 which causes tons of DRC violations between M1 PG nets and M1 routings inside std cell.
In my attached figures, (a)shows the right case, (b) shows the wrong case. I am wondering why (b) happens and in astro, can I set the width of M1 PG nets by myself?

Many many thanks in advance!

 

[linuxluo]

hi,
normally, not suggest using M1 for stripe. using upper layer for good power integrity.

 

[eexuke]

hi,
normally, not suggest using M1 for stripe. using upper layer for good power integrity.

Hi,
It's not the power stripe. The problem I described above occurs on basic M1 power/ground nets which connect all the power/ground nets of standard cells. For wide power stripes/rings, I always use higest or higher metal layers.

 

[research235]

Hello

I am not sure whether i can post here but did not find soem other topic. I am very new to Astro, i want learn this tool from very basic and not sure where to start. If only some one of you suggest me seom tutorial i can quick start on this .

Please suggest me some reading material or tutorials

Thnks in advace

Sing