Lithography fab process

[earthgod2504]

I have a question relating to fab process of semiconductor using lithographic process.
In this process, we need a lighting source (UV) to pass though a mask and project on the photo-resist.
So my question is for a particular IC, fab needs to have specific masks for that IC, is it right?
And, how do we have that mask or how it is produced?

Thanks,

 

[KlausST]

Hi,

For sure you need specific masks.

I'm not up to date with the technology.
It mainly depends on structure size.

As far as I know the mask is much bigger in scale and during lithography the structure is down scaled by optics.
Very precise and expensive optics, with very stable and expensive mechanics.

I'm sure there are many better informations in the internert.
Try wikipedia, google .... look for "semiconductor lithography". You will find links additional informations.

Klaus

 

[srizbf]

For every IC you must have specific mask. Many masks are preapred for each IC.

For each layer of fabrication a mask is necessary.
Masks are prepared in high scale 100...x etc and then they are photographically reduced to actual size.

 

[john blue]

Digital circuits starts from Hardware Description Language(VHDL/Verilog) -> Synthesized by a compiler corresponds to the foundry technology -> Generate netlist -> Layout based on that netlist. The layout that is given to the foundry is the final design from your side. The foundry then generates another dozens of masks based on your layout in line with their process. Analog, on the other hand, starts from Schematic which is drawn using Process Design Kit (PDK) that is given by the foundry. Then, its converted to the Layout just like any PCB.

 

[dick_freebird]

Mask fabrication is the step between design "tape out"
and the start of wafer fabrication. A separate facility
and usually company does this, the equipment is
altogether different from wafer fab and the product
is patterned glass plates (masks) for use in the wafer
fab.

Check out Photronics, the largest mask fab services
vendor.

 

[earthgod2504]

Thanks for all of your help