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  • Silicon wafer under a microscope

We manufacture photomasks and custom patterned optics for commerical, military and university applications.

Our Frequently Asked Questions (FAQ) page is updated regularly based on customer feedback. Please check back often.

Are you able to process 200mm wafers in your facilities?2018-01-16T00:07:17+00:00

Yes, we have the capability to work with 200 millimeter wafers.

Can I place multiple units on a metal sheet and cut them out?2018-01-10T20:58:45+00:00

Photo Sciences can place multiple units on a sheet and remove them to provide individual units.

Can Photo Sciences manufacture deposition/shadow masks in stainless steel?2018-01-16T00:08:33+00:00

At this time Photo Sciences does not have a stainless steel process. This is due to lack of demand.

Can you build glass in circular shapes?2018-01-16T01:04:44+00:00

Yes. Our glass shaping team can core drill inner and outer diameters. We can also create inside cuts, angles and radiuses. For simple square or rectangle products we use our dicing saw technology.

Can you process .1mm glass? (as thin as paper)2018-01-11T20:36:05+00:00

Currently, we do not have the equipment and tooling to work with .1 millimeter glass.

Can you provide measurements for what we would expect to have for the final dimensions of the total thickness, foil thickness, foil feature size, and stepped feature size? Is this customizable at all or are there specific process based dimensions that are used for every shadowmask?2018-10-10T18:07:45+00:00

The mask is composed of a “Base Substrate,” typically 0.005” Cartridge Brass ASTM B19, B36 with a top and bottom layer of Nickel foil ~7-15 microns in thickness per side. The top Ni pull back is roughly 70-microns per edge, the brass etch varies depending upon geometry layout. The bottom “Control side” layer is on nominal.

Do you accept other data formats than; DWG, GDS, DXF?2018-01-16T00:06:01+00:00

We also accept raster and vector files. In addition, we can work from drawings, sketches and simple descriptions. Currently, we are working on the upload site to allow a larger variety of formats.

Do you coat the gold on top of the nickel-covered brass? And with the Pyromark flat black paint, is that also a coating on top of the nickel? Also, what are the advantages of using the pyromark? I am planning on depositing titanium with evaporation using this mask; will the coatings/mask be able to thermally withstand the evaporation? If you have any recommendations as to what coating option we should use, please let me know.2021-02-19T21:16:22+00:00

We can encapsulate the substrate in Au, Ni, or both. Pryomark is an optical black coating for VIS and IR wavelengths. As far as temperature goes, the mask will withstand a broad range of temperatures, but can be warped depending upon deposition, temperature, and material. We would recommend testing first.

Do you have any recommendations for cleaning thinner shadowmask substrates? Are there processes that we should avoid using (i.e. sonication) for 0.002″ thick brass base substrates?2019-01-25T16:23:23+00:00

That really depends upon the type of material deposition. The mask is fairly robust and can withstand most cleaning methods as long as care is taken not to bend or deform the mask.

Do you have any tips/techniques for placing a shadow mask on top of the silicon substrate and clamping it down without a lot of scraping between the mask and substrate?2018-04-12T23:43:35+00:00

Typically, a pin alignment fixture is used and often made by the customer, but Photo Sciences can facilitate the process.

Do you offer sputtered ITO?2018-01-15T23:58:04+00:00

At this time, we do not have a process for sputtered ITO. This is due to lack of demand.

During deposition, would we mount the shadowmask control-side down or control-side up? In the end this would really be up to us right? I imagine that with the control side down we would definitely get sharper device feature edges.2019-01-25T16:25:48+00:00

Control side down.

How do you deliver the shadowmask? In what kind of package?2019-10-04T16:36:16+00:00

We deliver the masks sandwiched between glass. 

How is the edge profile of the patterned features? I see from the images on your website that the edge is very thin. Is that the nickel coating? How far does that thin feature extend, and is it enough to not reduce feature size if depositing at an angle?2021-02-10T22:56:58+00:00

Yes, the edge on the website is nickel coating. The backside (or blurb-side) is around 70 microns per edge, plus the thickness of material. The Control-side (or front-side) is nominal, maybe around 5-microns, but varies (depends on feature size).

How long does it take to get my photomask?2018-01-16T00:07:43+00:00

A 4 to 6-inch chrome mask will ship 48 hours after plots are approved and payment is received. 8-inch and iron oxide will ship in 72 hours.

How to apply the shadow mask on a sample? Should I just tape it on top of the sample surface?2021-03-09T17:28:19+00:00

Most of our customers use Kapton Tape. Some use weights.

I have features on my shadow mask design that need to be ~1mm away from the mask edge; is this possible to accommodate?2021-02-11T21:31:15+00:00

We need at least 1mm from the mask edge.

I see that your shadow masks are nominally brass with a nickel coating, with thickness varying from 0.002″-0.01″. Does this mean that the thickness of the mask can vary in thickness by this much over its area? Or are these the options of mask thickness we can choose from? If the latter, is 0.005″ the standard thickness?2021-02-19T21:17:46+00:00

5-mil and 10-mil standard thickness. We strongly suggest not going below .005” thick (very delicate).

I’m looking to fabricate some shadow masks to use in an electron-beam evaporator. I heard that the smallest opening you can achieve is 25µm. What about the spacing between the openings? Can they be made at 100µm?2018-04-12T23:46:01+00:00

The standard feature size, or opening, is 20 microns. Tightened feature sizes can be 10 microns or better, depending on the data provided.

If I need to order more of the same shadow masks, can the tooling charge be skipped next time?2019-10-04T16:35:42+00:00

Tooling charges are not charged for re-orders. 

In each of our shadowmask designs there are 4 thru-holes for mounting the masks onto a custom fixture we are making. That being said, if the nominal dimension is only in the foil (i.e. the base substrate dimension would be about 150um wider for the thru-holes), this wouldn’t really be ideal for mounting as I imagine the foil component would just deform. Would it be better to account for the addition?2019-01-25T16:37:39+00:00

We can adjust as necessary for the custom fixture thru holes for best fit.

Is edge roughness of a photomask related to the critical dimension?2019-01-30T16:24:45+00:00

The factors that determine the “edge quality” or smoothness is the C.D. and tolerance and tool.

Is the shipping included in the mask price?2018-01-16T00:06:43+00:00

Shipping is an additional cost which is determined by the customer.

PSI prefers to use (nickel-plated brass) shadow mask material. How often this was used for PVD sputtering process?2019-10-04T16:34:23+00:00

Our bi-metal shadowmasks are used in both sputtering, and evaporative systems.

What is a PCM?2018-01-15T23:46:31+00:00

PCM means process control monitor. This is a test pattern that we place along the edge of every mask. It contains several designs that allow us to quickly verify that the equipment and process remains within the required parameters.

What is the difference between, Iron Oxide, Quartz and Soda Lime?2018-05-09T19:10:15+00:00
There are several types of glass used for precision printing, the main types are:
  • Sodalime: Basically it’s window pane glass and cheap.
  • Borosilicate: Optical Glass – This is a common type of material for optical components.
  • Quartz: Generally used for UV photomask applications.
What kind of software would you suggest to design photomasks?2018-06-22T14:29:23+00:00

Klayoutklayout.de (It’s free)  A good layout tool but not a great editor but lots of strong features under the hood.

On the higher end… DW2000 from Designworkshop (Canada).

When I order photomasks I have an order form that I use to list my specifications (i.e what layers to use, critical dimensions, mask polarity, etc.). Is there analogous form for ordering shadow masks? If not, how should I list my mask specifications and what specific information should I be providing?2021-02-11T21:32:47+00:00

We don’t use a mask order form for shadow masks. We would just need how many you need? What is the smallest feature size on your patterns? What is the overall size of your part (OD)? What layers to use and any other helpful information.

When will I get my quote?2019-01-25T16:40:41+00:00

We will send you a quote within 24-hours (depending on the complexity of your order).

It helps us if you upload the design you have in mind to UPLOAD YOUR DESIGN so we can recommend the appropriate path for your type of product. Please let us know in the comments section (where you are uploading the file) the details of your order.

Which substrates can Indium Tin Oxide (ITO) be patterned on?2018-06-08T20:34:00+00:00

Which substrates can Indium Tin Oxide (ITO) be patterned on?

  • We can apply ITO to most hard surface subsrates (Glass, Si, Alumnia, etc…).

What is the range of thickness for these substrates considered max/min?

  • The common substrate thicknesses are 0.300mm – 0.250” .

Does Photo Sciences do small-scale orders?

  • Yes we do small scale orders.
Why would I choose a quartz substrate for my photomask?2018-05-14T15:29:32+00:00
Quartz has better UV optical properties and a lower TCE (Thermal coefficient of expansion), but it’s also expensive.
Why would I choose a soda lime substrate for my photomask?2018-05-14T15:31:03+00:00

It’s cheap and readily available and works great in the VIS range.

Why would I choose an iron oxide coating for my photomask?2018-05-14T15:35:08+00:00
Iron oxide is opaque to UV wavelength but transparent in the VIS range, which allows one to see through it to aid in alignment.
Will the control-side brass with Ni foil shadow masks have dimensions within tolerance of the mask drawings?2021-02-11T21:34:34+00:00

Yes, that is correct.

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