the name of the layers in cadence

Hi,
In cadence in layout editing I put a nmos transistor by create instance. is there any way that i understood the layers I mean to click a layer and it shows the name of it?
and do you have a pdf file to explain the layers for 0.18um?, I can not understand some of the layers by their name like c1!!
with best regards
Matin

The layers of any given process are defined in the Process Technology File, or more commonly called the "tech file". The tech file that you currently have attached to your library is listed near the top of the LSW window, and you will need to find this file in your directory structure in order to see how layers are being defined.
The manufacturer of the process you are using should be able to provide you with documentation on the layers and devices used.

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Just to add, I'm not aware of a layer C1 in any process I've ever used, so it would appear from the info you've provided here that you are not using the correct tech file for your desired process. The other case could be that you are simply using a student based tech file, and the layers are simply placeholders for real layers used in production.

There are often layers with no physical meaning, that the
CAD guys use for recognition, tagging, keepouts and so on.
And a real mask layer may be built from some superset of
layers / blocking layers / purpose-layers by Booleans and
operators (over/undersize/avoid). So it's not surprising if
you run across things that are not intuitive or have no
obvious 1:1 meaning.

What I've found a useful learning exercise, is to place and
flatten a "normal" device of each type. and then "roll it"
from X-Y to a X-Z orientation by stretching the polygons
to a roughly-right Z height from their original Y extents,
and build myself a cutaway view. You start with the more
obvious ones (well, active, S/D, poly, contact, metal) and
apply some mental Booleans of your own (like, (poly+!active)
hard-masks S/D to less than implant PR) and make your
device look right, classically. Then you will have these
"leftovers" to figure out, but now you have the context of
the basic device that can show you, perhaps, that C1 must
be contact because there is no other contact where you
need one, etc. (just an example).

Your foundry ought to publish, somewhere, what the mask
Booleans are in terms of PDK named layers. You can look
through those and find where "whatever" is being used,
and by its use deduce what it's meant for in layout. But
for some people, a visual view is more helpful, which is the
point of what I suggest above.