This is an incredibly large amount of material to remove with a FIB I doubt that it would be possible. If you wanted a 1um hole in a 1um thick membrane then a FIB would be the best. For a 0.2mm hole in 0.2mm thick glass use a laser. I have both FIB and laser machining experience.

How about a focused ion beam (FIB)?

Agree with Sean

Check out laser micro machining option as well, all you need is a CO2 or an excimer laser and a focused beam (can be done commercially as well)!!

This can be done with diode-pumped Nd:YAG lasers emitting sub-nanosecond pulses. The focusing parameters and pulse energy (typically in the range of a few mJ/pulse) should be carefully optimized for a crack-free drilling. The hole diameter in a 0.22-mm glass coverslip could be as small as a few tens of micrometers. The third harmonic at 355 nm will allow for smaller hole diameters and a better quality of the hole walls.

Thanks guys, let me see if there is any local lab equipped with this laser. We have two photon laser, but it is too weak for this purpose, i am afraid

I was about to recommend exactly what Sean Kirkpatrick said. FIB all the way!

This is an incredibly large amount of material to remove with a FIB I doubt that it would be possible. If you wanted a 1um hole in a 1um thick membrane then a FIB would be the best. For a 0.2mm hole in 0.2mm thick glass use a laser. I have both FIB and laser machining experience.

Thanks to Dr.Palash Gangopadhyay who provided most feasible information, it seems the following company can do this perfectly.

http://www.lasermicromachining.com/materials/glasses/index.php

It seems not wise to order commercial service, since we are still refining our design, so it costs too much, and may not be good. Is there any lab that use CO2 laser for cutting of glass available for collaboration?

Yo can do some fluorhidric acid etching; it seems simple because yo can make a polimeric mask, but the acid is very toxic!

For 1mm holes a dentist drill works perfectly. Maybe there exist a tool of 0.22mm, but I don't think so. Lithography mask + HF etch seems the best solution. The etch rate of HF is very high and selective. You just need a tiny amount of HF and a polypropilene (PP) container.

go to physics department and find a laser expert with either ns or fs laser. They can do it for you even with a submicro holes.

It is also possible to use micro waterjet machining to achieve this.

Thanks, guys, hi Nasser, is there an easy way to do lithography mask? HF can etch glass but in a glow way, it is hard to control the dimmension of etching.

iHi Junze, i checked our physics department and they dont have a laser for this purpose. Are you in such a lab?

hi Margareth, mwj sounds interesting, i just sent an inquiry to a company of this kind. thanks.

Still in search of help...

Dear Yajie,

The easiest way I know for making a mask is by printing an acetate sheet with a high resolution laser printer. With a high resolution printer this method becomes problematic only below 10 microns.

Yajie, I don't have this type of laser anymore. If you cannot find a short pulse at any wavelength or CO2 laser from a physics department. You may want to try Biomedical department. Any laser which has decent power can do this job.

Thanks Nasser, did you mean masking an acetate sheet by printer? What is next step if i want to mask a round thin glass coverslip? Thanks

see our paper: Precision glass machining drilling and profile cutting of by short pulse lasers in Thin Solid Films 477 (2005) 216-221

Hi there,

if there is a bit of money available, see if you contact

http://www.lmtb.de/lasertechnik/p_bearbeitung_de.php?id=2 (German)

http://www.lmtb.de/lasertechnik/p_bearbeitung_en.php (English)

They do glass as well.

Cheers, Hans

Thanks Suwas and Hans. I will check them.

There is Laser-induced backside wet etching.

http://www.aist.go.jp/aist_j/aistinfo/aist_today/vol05_10/vol05_10_p10_13.pdf

(Japanese)

Thanks Kiminori, it looks a cool tech!

We do it in different materials (ceramic, glasses, wood, steel, iron, etc.) with a CO2 laser. The way you arrange pulses and angles are critical for the quality of the edge of the hole.If you want a clean hole you need to combine it with a robot. If you want we can try it on your sample.

If laser drilling is not working you may try ultrasonic machining. It is used for high precision machining of brittle materials such as glass and the geometrical spec you gave are within the range of what can be achieved with this technique.

thanks Jean-pierre, sounds promising. How about availability?

ultrasonic machining can be a promising solution, but some lateral cracks could be seen on the top surface of holes. You can provide vibrations to the workpiece or the tool and pass sub micron size abrasive slurry b/w tool and workpiece. Ultrasonic transducers are easily available in the market, the one used for ultrasonic plastic welding can also be used. You wont require very high power transducers for micromachining purposes. The only main concern is the tool handling in this case. Smaller the tool, harder it will be to handle in micromachining. Moreover the alignment of the tool should be perfect. Wire electric discharge grinding will help you in developing the tool of required size. The size of the tool shall be less than the hole to be developed.

You can easily cut micro holes in thin glass plates using abrasive hot air jet. we were successful in cutting microholes of size 600 microns. If you reduce the size of abrasive and nozzle to 200 microns, then you can cut (drilling) holes of that size. Please refer: Machining of sodalime glass using abrasive hot ait jet: an experimental stydy, Jagannath N, Sadashivappa K, Somashekar Hiremath, Arun KV, Machining science and technology, Vol 16(4), 2012

Using a femtosecond laser it is certainly possible to drill small holes in coverslip glass. We have made slits and drilled holes in our lab in glass 0.17mm thick. Multiple burst of short burst works well and achieves better edge quality.

We do 500 micron holes in glass by simple micro-blasting. The nozzles as small as 140-micron are commercially available today, therefore machining 200-micron holes in glass with aspect ratio 1:1 is not a challenge. I attached a few photos of hole evolution and a simple setup.

Do the microparticles adhere to the glass? The circumference of the holes shows particles around. Does cleaning removes these particle? However, the holes look very precise.

Dear Dr. Nikumb,

Thank you pleasant comment. Those features on the hole edge are the impact craters. The holes were blasted by 27-micron (average) alumina particles. We could clearly see such large particles, especially at the top of shallow holes (I attached one (100-micron deep)). The particles embedding in glass may appear when particles smaller than 5 micron are used (erosion transits from brittle to ductile mechanism). When hole becomes deeper, particles starts to agglomerate at the bottom, and it limits the maximum depth, but those particles are always easy to blow out from the hole (at least for glass).

The hole edge and wall slope can be greatly improved by application of masks. I could demonstrate it, if someone make me those masks ))).

Thank you. Another nice technique to drill fine holes in glass!!