3X test - Objectives vs Lenses - Final Results Online

Have questions about the equipment used for macro- or micro- photography? Post those questions in this forum.

Moderators: ChrisR, Chris S., Pau, rjlittlefield

RobertOToole
Posts: 1613
Joined: Thu Jan 17, 2013 9:34 pm
Location: United States
Contact:

Post by RobertOToole »

Lou Jost wrote:I really like that you included the Mag.X. It is good to see what is possible, not just what is practical or easy. I lust after that lens!
Its gets worse once you find one! Now I really want the 8x/0.32 version Mag.x!

Super APO, Double Telecentricity, f/1.4, effective 12.5 at 8x. The Mity 7.5 is f/2.1 and Eff 17.86!

The 8x/0.32 would be pretty awesome pushed down to 5x!

Robert

RobertOToole
Posts: 1613
Joined: Thu Jan 17, 2013 9:34 pm
Location: United States
Contact:

Post by RobertOToole »

ray_parkhurst wrote:
RobertOToole wrote:...
The Metal markings look like they have a lot more depth than the poly marks.
Poly is below contact, which is below the metals. Poly and contact are both doped, so are quite thin, which is why the resolution is better. Metals are thick, so cannot be spaced as closely, and have worse resolution due to alignment, etching variation (under or over etching producing undercut or shorts), and grain boundary issues. Design rules for line spacings get larger as you go higher.
Thanks for the input Ray.

Any idea the difference in height could be between Poly and Metal?

If those are micron width markings, whats the height, fractions of a Nm?

I am a little surprised that the DOF of the Mity 50x got it all in one image.

Robert

ray_parkhurst
Posts: 2656
Joined: Sat Nov 20, 2010 10:40 am
Location: Santa Clara, CA, USA
Contact:

Post by ray_parkhurst »

RobertOToole wrote:
ray_parkhurst wrote:
RobertOToole wrote:...
The Metal markings look like they have a lot more depth than the poly marks.
Poly is below contact, which is below the metals. Poly and contact are both doped, so are quite thin, which is why the resolution is better. Metals are thick, so cannot be spaced as closely, and have worse resolution due to alignment, etching variation (under or over etching producing undercut or shorts), and grain boundary issues. Design rules for line spacings get larger as you go higher.
Thanks for the input Ray.

Any idea the difference in height could be between Poly and Metal?

If those are micron width markings, whats the height, fractions of a Nm?

I am a little surprised that the DOF of the Mity 50x got it all in one image.

Robert
Poly and Contact are sub-micron. Metals can be up to a couple microns thick but typically average around 1um. So if you have a 4-metal system, you're probably talking total height of a few um.

mawyatt
Posts: 2473
Joined: Thu Aug 22, 2013 6:54 pm
Location: Clearwater

Post by mawyatt »

Robert, Ray,

Sometimes processes have a thick and thin top metal, the thick is often used for inductors to improve the quality factor. The thick can be 5 microns.

During the era of this wafer we utilized a new process at Bell Labs that had a special thick gold top metal, it was 25 microns thick!! You can guess what it was used for!!

Best,
Research is like a treasure hunt, you don't know where to look or what you'll find!
~Mike

ray_parkhurst
Posts: 2656
Joined: Sat Nov 20, 2010 10:40 am
Location: Santa Clara, CA, USA
Contact:

Post by ray_parkhurst »

mawyatt wrote:Robert, Ray,

Sometimes processes have a thick and thin top metal, the thick is often used for inductors to improve the quality factor. The thick can be 5 microns.

During the era of this wafer we utilized a new process at Bell Labs that had a special thick gold top metal, it was 25 microns thick!! You can guess what it was used for!!

Best,
In my HEMT processes, we top-out around 3um thick for gold. As thickness increases, width and spacing rules must also increase, so these thick metals are only used for high current routing on the very top layers.

By appearance, the process for this wafer probably did not use thick metals, and likely only Al an alloy, so I'd still expect total thickness of only a few um at most.

AlxndrBrg
Posts: 72
Joined: Tue Jan 14, 2014 12:17 pm

Post by AlxndrBrg »

Great stuff - I am kinda missing the Lomo 3,7x though, from what I recall it handles being pushed down quite far, would be interesting to see how it competes with these real glass monsters ;)

Lou Jost
Posts: 4425
Joined: Fri Sep 04, 2015 7:03 am
Location: Ecuador
Contact:

Post by Lou Jost »

I've been using the Lomo on FF where it does very well (it is not so great on MFT). I tested it against the DiMage at 4x on FF and the Lomo won, even in the corners.

ray_parkhurst
Posts: 2656
Joined: Sat Nov 20, 2010 10:40 am
Location: Santa Clara, CA, USA
Contact:

Post by ray_parkhurst »

AlxndrBrg wrote:Great stuff - I am kinda missing the Lomo 3,7x though, from what I recall it handles being pushed down quite far, would be interesting to see how it competes with these real glass monsters ;)
I was wondering same thing. It should do well due to the low CA, though its NA 0.11 likely won't be competitive from raw resolution perspective. Same situation for the Inspec.x 105mm f4 3.5x lens with NA 0.1. Great coverage, low CAs, but won't beat the resolution of a high NA objective.

Post Reply Previous topicNext topic