Best microscope for wafer viewing - Page 1
Forum section: electronics / general

author: EEVblog
author_rank: Unknown
timestamp: March 15, 2015, 12:55:10 am
content: As the title says, what's the best microscope for viewing and more importantly video recording detail on silicon wafers and other really tiny detail stuff with excellent image quality?I'm thinking something like this coaxial light monocular scope perhaps with of course suitable video camera on top:http://www.ebay.com.au/itm/AmScope-H800-CL-Inspection-Zoom-Monocular-Microscope-w-Coaxial-Light-/400427943454?pt=LH_DefaultDomain_0&hash=item5d3b5d861eField of view 2.4mm @ 1920x1080 HD gives 1.25um resolution per pixel. if the optics are good enough, could even use a 4K camera.Thoughts and suggestions?

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: March 15, 2015, 01:07:05 am
content: For die details you're well into "proper" microscope territory - 50-1000x total mag (objective x eyepiece)You want something that has a beamsplitter, so it fires light through the objective - sometimes called a metallurgical microscope - as with high magnification the working distance is vanishingly short - virtually touching, so there's no room for external light, and as the subject is opaque you can't fire light through the subjectx100 objectives typically need oil between objective and subject.

author: Rupunzell
author_rank: Frequent Contributor
timestamp: March 15, 2015, 06:43:47 am
content: Suggest the industry standard for a long time. Leitz Ergolux. These are designed for wafer inspection using bright field & dark field illumination with infinity corrected objectives and ICR prism option can be had if needed. The standard objectives for these are NPL, the higher quality objectives are Fluotar which are "semi APO". For camera imaging, make sure to get the ergo trinocular tube specifically designed for optical viewing and a camera port.They look like this:http://www.ebay.com/itm/Leitz-ergolux-microscope-/291401830681?pt=LH_DefaultDomain_0&hash=item43d8e71119Ergolux in good condition with a complete set of proper optics and lighting can be purchased for $1000 or less USD depending on condition optics and all that. Shipping will be expensive due to it's extremely fragile nature and weight.. nearly 50 pounds of high precision German made optical instrument. Made in China is not the way to go here.The alternatives are a good metallurgical microscope with bright field / dark field made by Zeiss, Nikon, Olympus, Reichert, Zeiss Jena or Leica Micro Systems. These often do not have a large enough stage with the stability and movement range required for wafer work. These do meet the optical and lighting requirements and are adaptable for camera set ups.IMO, it is a waste of time and all related to use anything less for this kind of work. Like all high quality instrumentation, they are designed and intended to be serviced and stay in service for a very long time with proper ergonomics and user satisfaction.BerniceQuote from: EEVblog on March 15, 2015, 12:55:10 am

author: Rupunzell
author_rank: Frequent Contributor
timestamp: March 15, 2015, 06:55:29 am
content: Immersion oil is nto typically used for this kind of microscope work. A 100X objective + 10X eye piece yields 1000X magnification which is enough for wafer work. Oil immersion objectives are common for transmitted biological microscope work as the transition from glass slide to air to objective's first element becomes a significant resolution limiter due to difference in refractive index. Oil immersion helps to reduce this loss.What matter in microscope optics is resolution, contrast, color correction and image distortion. Basic magnification is easy to get, resolution, contrast, color correction with low image distortion is difficult. Far more difficult is achieving all four with a good illumination system.BerniceQuote from: mikeselectricstuff on March 15, 2015, 01:07:05 am

author: coppice
author_rank: Super Contributor
timestamp: March 15, 2015, 06:59:09 am
content: Modern wafers only look interesting when you use an electron microscope.

author: EEVblog
author_rank: Unknown
timestamp: March 15, 2015, 08:37:38 am
content: Quote from: Rupunzell on March 15, 2015, 06:43:47 amICR Prism?Does anyone have a link to a manual or brochure for these Leitz Ergolux?

author: EEVblog
author_rank: Unknown
timestamp: March 15, 2015, 08:45:01 am
content: This Amscope one looks suitable too:http://www.ebay.com.au/itm/40x-800x-Metallurgical-Microscope-w-Polarizing-Features-5MP-Camera-/141598858149But always, those USB cameras are pretty crap at video, but could plug in a real camera.

author: EEVblog
author_rank: Unknown
timestamp: March 15, 2015, 09:13:16 am
content: Quote from: Rupunzell on March 15, 2015, 06:43:47 amYup, shipping will be the killer on that for sure.

author: SeanB
author_rank: Super Contributor
timestamp: March 15, 2015, 09:43:13 am
content: Only $200.............

author: rs20
author_rank: Super Contributor
timestamp: March 15, 2015, 09:57:26 am
content: Quote from: EEVblog on March 15, 2015, 08:45:01 amThat one looks far superior to me, it appears to use real, standard objectives, including a 50x one. This is important, because you're getting quite a lot of microscope for your money there, which means that the included objectives might not be A+, Full HD, distortion-free ultra-objectives. So just like you're suspecting that you might want to swap in your own camera, you may wish to (ultimately, if you decide you want to) buy an objective specific to your needs (just like a photographer chooses a lens specific to his/her needs -- this analogy is very apt, a lens for an SLR camera is technically termed the camera's objective lens, they are one and the same thing*). The more expensive an objective, the less the aberration, the higher the effective resolution, and the lower the distortion -- just like SLR lenses.* In fact, I made a microscope-objective-to-SLR adapter a while back. A standard microscope thread on one end, a Nikon lens mount on the other, and 160mm of plain old air in between. Using some objectives that I got from surplus shed optics (made in india, 4 for $20 IIRC), I got some lovely, if not full-HD, photos of the TFT transistors in a TFT monitor (had to take the monitor apart to see it; the working distance is so shallow that the front glass on an LCD is too much!). It was a massive pain to use because I had no fine adjustment knob, which is why I'm not suggesting you use the same approach. I only tell this little story as a way to make it crystal clear that a microscope is a fairly dumb, but precisely moveable tube. The camera and the objective are the stars of the show, so make sure they're both interchangeable.

author: EEVblog
author_rank: Unknown
timestamp: March 15, 2015, 10:19:43 am
content: Quote from: rs20 on March 15, 2015, 09:57:26 amAmscope have a very good rep on the forum it seems, at least for their lower magnification stereo optics.Claim the use the same production line as the big boys, not sure in what respect if that is true.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: March 15, 2015, 10:45:07 am
content: Oh, and it's is pretty much essential to have an x/y stage

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: March 15, 2015, 11:03:09 am
content: Has anyone found a site that explains the various terms and jargon of microscopes in plain english ?

author: coppice
author_rank: Super Contributor
timestamp: March 15, 2015, 11:06:05 am
content: Quote from: mikeselectricstuff on March 15, 2015, 11:03:09 amIf you go to the web site of a maker of many types of microscope, they can't even properly explain what makes each model special.

author: EEVblog
author_rank: Unknown
timestamp: March 15, 2015, 12:38:22 pm
content: Quote from: mikeselectricstuff on March 15, 2015, 11:03:09 amNope!Doesn't even seem to be consistent across manufacturers from what I can gather.It seems you are expected to be "in the know" about all aspects of what everything does and why and what for from each manufacturer.There seems to be about a dozen different types of compound microscope types, and just the lighting systems and the optics and paths and technology used for that alone seem to confuse the various types of practical uses with the actual technical aspect of how the lighting itself works.Crazy stuff.

author: EEVblog
author_rank: Unknown
timestamp: March 15, 2015, 12:41:23 pm
content: Quote from: mikeselectricstuff on March 15, 2015, 10:45:07 amYes, that Amscope one seems to have a bottom access vernier for that, but it doesn't tell you it's actually X and Y, or if it's even a precision vernier etc.I have been looking at various 3rd party x/y stages just in case more precision is needed.Usually they have course and fine verniers for each axis, so not sure how the amscope one works.

author: KJDS
author_rank: Super Contributor
timestamp: March 15, 2015, 12:47:02 pm
content: What resolution do you need? Seeing details of a 10nm RAM will require quite a lot more than an old transistor on a process measured in microns.I did some work with some power diodes that I could all the detail without my glasses on, but the smallest lateral dimension was 3mm.

author: EEVblog
author_rank: Unknown
timestamp: March 15, 2015, 12:49:43 pm
content: Quote from: EEVblog on March 15, 2015, 12:41:23 pmOn second look is has this spec:QuoteSo I assume the vernier they are referring to is the stage and not the focus, which by implication is both X and Y.If that is true then that sounds good enough.

author: EEVblog
author_rank: Unknown
timestamp: March 15, 2015, 12:57:57 pm
content: Quote from: KJDS on March 15, 2015, 12:47:02 pmDon't know exactly, I've just wanted a good quality microscope to make good quality videos with for a long time.I already have my video camera macro lens that does a half decent job down to 13mm field of view. And my Tagarno goes down to 10mm field of view with insane working distance. Both of those are great for general purpose teardowns.But I'd like to have something that does say 1mm field of view for general silicon dies and other objects for teardowns etc.A 1mm field of view for example will give 0.5um pixel resolution on a full HD video. That should be plenty for general die structure and other small object inspection.

author: EEVblog
author_rank: Unknown
timestamp: March 15, 2015, 01:10:26 pm
content: Quote from: EEVblog on March 15, 2015, 12:57:57 pmSpeaking of which, FOV calculations for the Amscope one are:The WF16X eyepieces are 11mm FOVFor the objectives supplied:x5: FOV = 11mm / 5 = 2.2mmx10 FOV = 11mm / 10 = 1.1mmx50: FOV = 11mm / 50 = 220umI'm going to assume the x50 is not going to be that good an optical quality (and likely extreme working distance limitations, i.e. practically touching, so flat objects only). So the x10 objective should be quite usable for starters.And I can always buy a top quality x20 or even x50 objective.Although Amscope claim the objectives are plan objectives, so should be flat across most the visible area and gives the best working distance. How much remains to be seen.But that's optical view, not sure what that translates to into the trinocular camera port?

author: rs20
author_rank: Super Contributor
timestamp: March 15, 2015, 01:52:42 pm
content: Quote from: EEVblog on March 15, 2015, 01:10:26 pmAs for what the camera sees, these aren't infinity-corrected objectives*, so it's quite straightforward (once you've spent a while studying all this :-)): the eyepiece is not involved at all, the objective projects its image directly (well, via some mirrors/prisms) on the camera sensor, but 5, 10 or 50 times bigger than real life. The field of view of the supplied camera is 5.70mm(H) x 4.28mm(V), but there's a 0.5X reduction lens on it which makes it effectively 11.4mm x 8.56mm; divide that by 5x, 10x, or 50x to see the field of view that you'd get. Since your objective has a field of view of ~11mm, and the camera field of view is ~11.4mm wide, the answer is, as you would hope, almost exactly the same as the calculations you gave above. The pixel size is 3.2um, which is actually 6.4um if you factor in the reduction lens, again, divide by 5, 10 or 50 to see the "real" pixel size (remembering that each pixel is either R, G, or B, so your true resolution is considerably worse than this.)* With infinity-corrected objectives, the image is formed by a lens in the tube; the magnification factors given by an infinity-corrected objective is stated under theassumptionthat the tube lens has a 200mm focal length. If it's not, you have to scale the objective magnification accordingly, a x10 infinity objective with a 100mm tube lens is really only x5.

author: Rupunzell
author_rank: Frequent Contributor
timestamp: March 15, 2015, 05:08:10 pm
content: ICR is Leitz's version or brand name for differential interference contrast (DIC) microscopy.http://www.microscopyu.com/tutorials/java/dic/reflectedwavefronts/Ergolux manuals can be ordered from one of the many independent Leitz service folks. Leitz-Leica was a highly customer service oriented organization before they were taken over by Danaher (just like Tektronix, Fluke and...) after which became Leica Micro Systems. Much like what happened to Tektronix, Fluke and... post take over, the company was never the sameHere is a short about Leitz microscopes including the Ergolux:http://www.buntgrp.com/used_microscopes.htmMicroscopes like these can be configured to most any requirement. They are modular and have highly interchangeable parts to achieve the desired configuration.Serious microscopes are much like serious test gear made by hewlett packard, Tek and others that were designed to the limits of physics, in the case of optical microscopes, the behavior of light, ultra precision optics manufacturing, highly specialized optical coatings and machined metal parts accurate to wave lengths of light. This is the difference between a proper high quality microscope and mass market low cost microscopes. Good optical microscopes when new are easily 5 to 6 figures of USD. Back when microscopes were mostly built to this level of quality, durability and performance, they were intended to be in service for decades, used by skilled personal who understood how to use them and care for them.BerniceICR Prism?Does anyone have a link to a manual or brochure for these Leitz Ergolux?

author: Rupunzell
author_rank: Frequent Contributor
timestamp: March 15, 2015, 05:15:10 pm
content: Still a toy..Limited lighting options, the mechanicals are rink-dinky unstable and totally unsuitable for high magnification. It appears to be transmitted light (useless for viewing wafers) and only bright field lighting, no dark field and no infinity corrected objectives. All of which are serious limitations for lighting and viewing options. Those glass slide clips are a joke as those are intended for glass microscope slides and they are a total pain in the arse to use. No decent biological transmitted light microscope today has those clips.Consider for a moment objects being view with a microscope are typically microns in dimension. This means the related mechanical bits must have similar precision to impart any useful microscope stage movement.BerniceQuote from: EEVblog on March 15, 2015, 08:45:01 am

author: Rupunzell
author_rank: Frequent Contributor
timestamp: March 15, 2015, 05:17:41 pm
content: Spend for proper shipping cost. This is an investment for high quality instrument. $200 USD for shipping is not high or extreme considering what is being transported.BerniceQuote from: EEVblog on March 15, 2015, 09:13:16 amYup, shipping will be the killer on that for sure.

author: Rupunzell
author_rank: Frequent Contributor
timestamp: March 15, 2015, 05:19:30 pm
content: Here are two.http://www.olympusmicro.com/index.htmlhttp://www.microscopyu.com/tutorials/BerniceQuote from: mikeselectricstuff on March 15, 2015, 11:03:09 am

author: Rupunzell
author_rank: Frequent Contributor
timestamp: March 15, 2015, 05:39:54 pm
content: For generalized microscope images, the Zeiss Ultraphot is quite desirable to this day.http://www.optovid.de/mikroskope-und-laborgeraete/Auflichtmikroskope/-Ultraphot_III-1396886629.htmlEach year Nikon run a "small world" image competition.http://www.microscopyu.com/smallworld/gallery/index.htmlBernice

author: EEVblog
author_rank: Unknown
timestamp: March 15, 2015, 10:49:04 pm
content: Quote from: rs20 on March 15, 2015, 01:52:42 pmThat's for the supplied camera (I'm looking to buy one without that camera.What about if I plug on my own Sony NEX-5T?

author: EEVblog
author_rank: Unknown
timestamp: March 15, 2015, 10:53:50 pm
content: Quote from: EEVblog on March 15, 2015, 10:49:04 pmAh, got it:http://www.ebay.com.au/itm/SONY-NEX-3-NEX-5-NEX-7-DIGITAL-CAMERA-LENS-ADAPTER-FOR-23-30-mm-MICROSCOPES-/261306702512x2 widefield equivalent to the x10 eyepiece

author: EEVblog
author_rank: Unknown
timestamp: March 15, 2015, 11:04:50 pm
content: Quote from: Rupunzell on March 15, 2015, 05:15:10 pmHave you tried the Amscope? or are you just guessing?I don't need super high magnification, just reasonably high and good enough for some HD video.Of course I don't expect it to be as good as an industry leading one.QuoteWhy is the lighting on this useless for wafers?According this:http://www.microscan.com/en-us/technology/machine%20vision%20lighting/brightfieldanddarkfieldlighting.aspxBrightfield lighting is ideal for bright and shiny reflective surfaces, or which wafer and other metal stuff like bond wires etc will be.It specifically says it's suitable for wafer viewing.QuoteAgreed. I'm assuming they removable.And I'm not after a biological microscope, I'm after a metallurgical one. I will be viewing dies, hybrids, bond wires, PCB's in fine detail etc.

author: rs20
author_rank: Super Contributor
timestamp: March 15, 2015, 11:22:09 pm
content: Quote from: EEVblog on March 15, 2015, 10:53:50 pmNice! It's funny how your NEX-5T has a four-times (per side) larger sensor than the Aptina, so they stick a 2x instead of a 0.5x lens on it and it again, turns out roughly the same field of view as the x10 eyepiece.[Just throwing it out there] If only you had a camera with a ~11mm wide sensor, you wouldn't need to use any adaptor at all (1x = plain empty tube, unless they're doing something more complicated than necessary), and could avoid the (admittedly minimal) risk of the camera lens adapter worsening your image quality. Digital zoom is when you use only part of your sensor. Makes me wonder if using your 23.5mm wide NEX-7 sensor with anoptics-free "1x" adapterand simply using the digital zoom of the camera would give better quality overall. Possibly an interesting experiment for $13.

author: EEVblog
author_rank: Unknown
timestamp: March 16, 2015, 12:27:05 am
content: Quote from: rs20 on March 15, 2015, 11:22:09 pmPerhaps, yes I'd probably try both.My NEX VG30 video camera also have the same E-mount and sensor size. But it's big and bulky though, so probably no advantage in using that over the NEX 5T

author: Rupunzell
author_rank: Frequent Contributor
timestamp: March 16, 2015, 03:46:43 am
content: Have you tried the Amscope? or are you just guessing?I don't need super high magnification, just reasonably high and good enough for some HD video.Of course I don't expect it to be as good as an industry leading one.*No guess, Tried them at a local microscope dealer and purchased them used with dismal satisfaction. The qualifier here, experience & skilled user of research and lab grade microscopes. For those new to microscopes, Amscope and similar are going to be a LOT better than nothing.*What troubles me about these made in China microscopes is their overall quality and optical performance. The bodies are made of very soft and low quality aluminum in critical parts with pot metal zinc castings for where they can get away with using it. The knobs are crack prone styrene plastic, the screws are soft with poorly formed threads and heads, the mechanical design is poor. Optically, there is geometric distortion, axial and lateral color problems, field flatness problems and overall low contrast, flare prone and low resolution. This is visible in the sample images posted by the ebay seller.QuoteWhy is the lighting on this useless for wafers?According this:http://www.microscan.com/en-us/technology/machine%20vision%20lighting/brightfieldanddarkfieldlighting.aspxBrightfield lighting is ideal for bright and shiny reflective surfaces, or which wafer and other metal stuff like bond wires etc will be.It specifically says it's suitable for wafer viewing.*Bright field axial light system requires a high quality beam splitter with a very good light system behind it. Beyond this, the objectives need to have low internal reflections to produce a good image.*Here are some sample images made using various lighting system with a high quality microscope. Note how the different lighting systems affect the image details presented. These are old 4000 series logic and single device dies. Smaller geometries will impose even greater demand on the optical and lighting system.https://resnicklab.wordpress.com/tag/4000-series/*Have a look at their microscope hardware..https://resnicklab.wordpress.com/laboratory-resources/microscopy/*Note their Zeiss Ultraphot III, circa late 1960's to 1970's."Microscopes have been around for about 500 years- they are one of the oldest scientific instruments that are still in regular use. Obviously, the microscopes we use today greatly outperform the microscopes used by Hooke and van Leeuwenhoek, but you may be surprised to learn that the world’s best microscopes from the 1960s work as well as state-of-the-art microscopes made today."That statement is why investing in a high quality lab or research grade microscope is worth while and staying away form hobby-entry microscopes is recommended by those with lots of microscope experience.Quote*HD video will place high demands on the microscope's optical and lighting system. This will become apparent upon the first imaged made with a less than high quality microscope.*Magnification is not the important number for microscopes, Image resolution (directly related to NA for a given magnification), contrast, color rendition-color correction, geometric distortion and other non-specificed factors are more importing than the simple magnification number. Adding to this, system flexibility and ability to adapt to imaging requirements, and overall mechanical quality matters.. a great deal.*This comes from being an owner of a Leitz Ergolux, Zeiss stereo microscope and others. This all began during my years of working with microwave hybrids and trying to understand how die geometry of discrete devices relate to electrical specification and behavior of these devices. Using a high quality microscope is a basic tool for this work.*Know there is a learning curve to using a microscope and the images viewed using properly adjusted eye pieces to your vision will always be better than recorded images or images presented on a video monitor.Bernice

author: EEVblog
author_rank: Unknown
timestamp: March 16, 2015, 04:38:45 am
content: Quote from: Rupunzell on March 16, 2015, 03:46:43 amOf course. But all I want to do is shoot some youtube videos.I currently use a $30 macro lens on the video camera I use for all my teardown closeups that has some horrible distortion, yet virtually no one has ever complained about it, it's good enough for the job.

author: Rupunzell
author_rank: Frequent Contributor
timestamp: March 16, 2015, 04:41:06 am
content: If all are happy with the results of this set up, stay with it.No reason to change..at all.BerniceQuote from: EEVblog on March 16, 2015, 04:38:45 am

author: EEVblog
author_rank: Unknown
timestamp: March 16, 2015, 06:02:02 am
content: Quote from: Rupunzell on March 16, 2015, 04:41:06 amI am, but I'm not replacing this, I need something with more magnification for smaller stuff. My macro lens only has 13mm FOV.

author: EEVblog
author_rank: Unknown
timestamp: March 16, 2015, 06:25:16 am
content: So who votes for the Leitz Ergolux?http://www.ebay.com.au/itm/LEITZ-ERGOLUX-Brightfield-MICROSCOPE-/141592560075

author: rs20
author_rank: Super Contributor
timestamp: March 16, 2015, 06:30:45 am
content: Quote from: EEVblog on March 16, 2015, 06:25:16 amI cast one untrained, uneducated vote for the Leitz, that brand name has got to be worth something alone!

author: Rupunzell
author_rank: Frequent Contributor
timestamp: March 16, 2015, 06:47:38 am
content: There is an entire macro-micro world of discovery waiting for you.Seriously consider venturing into it with the proper tools.More magnification/smaller FOV means increased resolution and all related that comes with that requirement.Know the specific trade offs of each microscope system and these trade offs fit with light and optical limitations.Suggest doing some study, reading up on this topic before making any purchase. There are many resources on microscopy on the web and in written literature. Another possibility would be to visit your local University and speak with professors who work with microscopes. They can help a great deal with information and real live demonstrations of all this microscope stuff.There are no easy-instant-low cost solutions, they are all a set of trade-offs which the user makes their peace with and lives with.BerniceQuote from: EEVblog on March 16, 2015, 06:02:02 am

author: EEVblog
author_rank: Unknown
timestamp: March 16, 2015, 07:00:34 am
content: Quote from: Rupunzell on March 16, 2015, 06:47:38 amI would love to do all that, but I don't have the time nor the inclination. I've already done enough that tells me the Amscope one will, with quite high likelihood do what I want.The only choice is to go something better 2nd hand with the Leitz ergolux instead.I just want a half decent microscope that I can attach an existing video camera too so I can get some teardown shots I haven't been able to get before.

author: Rupunzell
author_rank: Frequent Contributor
timestamp: March 16, 2015, 07:12:30 am
content: CAUTION !!!The objectives are bright field only. These objectives do not support dark field. These are not the ideal objectives for the Ergolux.These are what it should have, NPL - DF, not plain NPL.http://www.bmisurplus.com/uploads/product_addl_images/30136_1_.jpgOne of the five objectives are missing and these are NPL objectives which are OK. The illuminator module is 0.8X. Two versions were offered, 0.8X and 1X. This one has the standard stage which has a coaxial controls for X-Y.Early versions of the Ergolux has RMS threaded objectives. Later versions of the Ergolux has larger thread size objectives and are offered in APO. These also have the objective motor controls as buttons on the front.http://www.fabsurplus.com/sdi_catalog/salesItemDetails.do?id=21879Ergolux were often configured for X-Y measurement and film thickness measurement as required.BerniceQuote from: EEVblog on March 16, 2015, 06:25:16 am

author: EEVblog
author_rank: Unknown
timestamp: March 16, 2015, 07:18:12 am
content: Quote from: Rupunzell on March 16, 2015, 07:12:30 amSo ultimately what does that mean in the real world of what I want it for?What's the problem?The other one on ebay has both? (but no original light source )QuoteNPL is still much better than an Amscope optics, right?QuoteIs that good or bad?QuoteSo both units on ebay are the old model? Is this a problem?I just want to make sure I'm not buying something that will be useless for my needs because it's missing something, has a wrong thingamejig etc.I'm pretty darn sure the Amscope will do exactly what I want, so it's the safe but probably lower quality optical option.

author: Rupunzell
author_rank: Frequent Contributor
timestamp: March 16, 2015, 07:23:51 am
content: Other choices:Leitz-Leitz M420. These fit between the 13mm FOV and higher magnifications offered by the Ergolux system. Very high optical quality, expensive to this day due to demand and their specialization of which there are limited choices.http://www.savazzi.net/photography/wild_leica_m420.htmStereo Zoom with a Photo tube. These offer up to a few 100X with reasonable image quality. The main features to stereo zoom microscopes is depth perception and objective to subject distance.http://www.nikon.com/news/2009/0709_smz745t_01.htmBerniceQuote from: EEVblog on March 16, 2015, 07:00:34 am

author: Rupunzell
author_rank: Frequent Contributor
timestamp: March 16, 2015, 07:34:27 am
content: Quote from: EEVblog on March 16, 2015, 07:18:12 am

author: rs20
author_rank: Super Contributor
timestamp: March 16, 2015, 09:52:27 am
content: Quote from: Rupunzell on March 16, 2015, 07:34:27 am<Massive grain of salt>Hold on, excuse my ignorance, but how can this be a bright field image:?https://resnicklab.files.wordpress.com/2013/04/dsc06313.jpgCorrect me if I'm wrong, but brightfield means that the light is underneath the sample, shining through it, so very loosely speaking you're looking at a silhouette. Light can't shine through a chip, so the image would just be black/blank/absent, right? Or is that chip completely de-potted, and are chips actually transparent once you've removed all the plastic? <question invalid if my understanding is incorrect>Is Dave planning to de-pot things to that extent?</question>Furthermore, one has to be cautious with the term "dark field" imaging, because it can refer to two different things:A. "Traditional" dark field [TODO: figure out the real correct term]: Just like traditional bright field imaging, but a little dark disc prevents light from the source entering the objective directly on-axis. This means that light has to bounce off the specimen for it to be make it to the sensor/eyepiece, so the image is a bright sample on a dark background (background = "field"). Since light is likely to still be hitting the objective, but out of its field of view, the objective must be of enough quality to dispose of this light efficiently; much like how good quality photographic lenses avoid lens flare when the sun is out of frame. This quality/ability grants an objective the -DF suffix, meaning suitable for dark field. Crucially, if you stick a PCB or a full-sized DIP chip on the stage, this technique is going to fail just as badly as light field imaging, because the light is still coming from underneath (just slightly off-axis), and the PCB/chip will still completely block the light.B. Episcopic or (Epi-) illumination, whereby light is actually sent through the objective itself onto the sample, from above. This obviously puts even more strenuous demands on the objective than dark field imaging, and requires some crazy smarts inside the telescope tube. Can be used with or without polarization, just like the other two methods above.Fortunately the AMScope has Epi illumination. Not sure what the deal is with the Leitz Ergolux, can't tell from the specs whether it supports Epi.So again, what's the full story behind those two images? I just don't understand how one can be conventional brightfield, unless I'm missing something. I'm wondering if they're both epi, but the colourful one is phase/polarization something something. Or maybe one is conventional epi, and the other is darkfield, using a chip that's been cut into a very small piece so that light can bounce off the shiny metal of the objective and back down to the sample. What on earth is epi-brightfield? It's mentioned in your link, and seemingly nowhere else on the internet. Sounds like a contradiction in terms to me. Bernice, please correct me! I want to be sure I'm understanding this correctly.</Massive grain of salt>

author: EEVblog
author_rank: Unknown
timestamp: March 16, 2015, 10:41:03 am
content: Quote from: Rupunzell on March 16, 2015, 07:23:51 amI have no need for depth perception. The goal is to shoot video and that's basically it.A monocular coaxial one I posted originally would be fine.

author: EEVblog
author_rank: Unknown
timestamp: March 16, 2015, 10:42:57 am
content: Quote from: Rupunzell on March 16, 2015, 07:34:27 amI posed the specs which seems to imply it does have x-y stage controls. Whether they are precision verier or not I don't know.

author: EEVblog
author_rank: Unknown
timestamp: March 16, 2015, 10:48:00 am
content: Quote from: rs20 on March 16, 2015, 09:52:27 amNope. I have no need for a bottom light source that I can foresee.QuoteI'm also somewhat confused by this.With the Ergolux for example, what is that joystick type control on the light that is presumably in series with the light source at the back?Rupunzel talks about objective that support darkfield and lightfield, if so how does that work inside the objective lens? and do you simply change the objective lens and bingo you go from darkfield to lightfield?Any other light controls on the Ergolux that do other stuff?

author: EEVblog
author_rank: Unknown
timestamp: March 16, 2015, 10:52:48 am
content: Quote from: rs20 on March 16, 2015, 09:52:27 amI assumed the Ergolux does because the light is at the back that goes into the main tube above the objective?The Amscope one also comes with various filters etc and certainly does have light coming through the objective as you say, which seems to go under severnal names, not just Epi?This is why I'm almost 100% confident the Amscope will do what I want, at least in terms of actual usable image. The only unknown is the actual image quality and the x-y stage movement precision (ebay listing mentions 0.1mm/div?).

author: EEVblog
author_rank: Unknown
timestamp: March 16, 2015, 11:01:31 am
content: This Amscope ones comes with both top and bottom light sources.http://www.ebay.com.au/itm/40x-2000x-Trinocular-Polarizing-Metallurgical-Microscope-w-T-B-Lights-/381186828518I'm not sure why it lists 5 "metallurgical magnification", plus 5 "polarising magnifications", plus 7 "transmitted application settings"What the deal with all those?

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: March 16, 2015, 11:07:21 am
content: Quote from: EEVblog on March 16, 2015, 11:01:31 amDifferent permutations of objectives and eyepieces I think - says it comes with 2 sets of eyepieces

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: March 16, 2015, 11:12:29 am
content: Btw what does "plan" mean in the context of objectives?

author: Sbampato12
author_rank: Regular Contributor
timestamp: March 16, 2015, 11:23:47 am
content: I've used a metallurgy microscopy to take some photos and videos from a ic wafer (old one):photos:https://www.flickr.com/photos/126938778@N07/it was a Zeiss (AxioImager A1m), with 20x 50x 100x 500x and 1000x magnification options. I've never used the 1000x, because I've never used imersion oil technics.With 500x I've been able to read some texts in wafer, and see some details.You will need, certainty, a trinocular (for the camera), a x-y positioner (capable of small changes, smooth) and a good light source.

author: coppice
author_rank: Super Contributor
timestamp: March 16, 2015, 11:26:42 am
content: Quote from: rs20 on March 16, 2015, 06:30:45 amI wouldn't rely too much on the Leitz name. They have produced some of the best optical instruments around - including microscopes, binoculars, and telescopes - but they've also made some real stinkers. that people hate.

author: EEVblog
author_rank: Unknown
timestamp: March 16, 2015, 11:52:05 am
content: Quote from: mikeselectricstuff on March 16, 2015, 11:12:29 amIt means that the image will be in focus over most (>95%) of the image, i.e. "flat field"They are the best ones to get.

author: rs20
author_rank: Super Contributor
timestamp: March 16, 2015, 11:53:07 am
content: Quote from: mikeselectricstuff on March 16, 2015, 11:12:29 amFor once, I don't need to prefix my answer with "err someone correct me if I'm wrong, not sure about this"!Plan refers to flat-field correction, which means that the focal plane is flat. Put another way, field curvature is minimized. Essentialy, if you're looking at something flat (like, I dunno, a wafer), it means that you can focus the entire thing at once. Without flat-field correction, you have to fiddle with the focus knob to get either the centre, or the edges of the wafer in focus, but you can't have both at the same time. With a plan objective, you set the focus once and it's all in focus at the same time. Plan isn't so useful if you're taking images of things that aren't flat*, or (to a lesser extent) if you're using the microscope with your own eyes, since fiddling with the focus knob becomes second nature over time. However, Plan is a highly desirable feature for photomicrography of silicon wafers, it's hard to contrive a more appropriate use case!Ref:http://www.microscopyu.com/tutorials/java/aberrations/curvatureoffield/Further reading:http://www.microscopyu.com/articles/optics/objectivespecs.htmlUnfortunately, some digital image processing muppets have come along and used "flat-field" correction to refer to the process of looking at a CCD and correction dead pixels and vignetting. So search for "flat-field correction microscopy" to get the right concept.* Indeed, if you're taking a microphotograph of the surface of a tiny, tiny little bowl/dish, a non flat-field corrected objective might actually be superior, since the focus surface follows the surface of the bowl! But obvs you'd never arrange for that, I only point this out to help illustrate what an objective/lens with a non-corrected field is. Plan is the best 99.9% of the time.

author: EEVblog
author_rank: Unknown
timestamp: March 16, 2015, 11:54:50 am
content: Quote from: mikeselectricstuff on March 16, 2015, 11:07:21 amThe eyepieces won't have any effect on how the image lit/displayed etc, just what the final magnification is.It's the objectives that do all the magic.

author: EEVblog
author_rank: Unknown
timestamp: March 16, 2015, 12:06:52 pm
content: Quote from: EEVblog on March 16, 2015, 11:52:05 amOh, and plan objectives can have a bigger working distances. How much that matters in practice at these sorts of magnifications levels I don't know.

author: rs20
author_rank: Super Contributor
timestamp: March 16, 2015, 12:17:08 pm
content: Quote from: EEVblog on March 16, 2015, 11:01:31 amBack to taking guesses -- it would appear to stem from the fact that it comes with 3 "metallurgical objectives" and 4 "achromatic objectives" (even though the metallurgical objectives are themselves achromatic; I think the second row should have been called "non-metallurgical" or "transmission/brightfield".Metallurgical Objectives: Plan Achromatic 5X, 10X, 50X (S) <-- 10x is double 5x, so there's two ways to achieve 100x overall magnification: 5 * 20 and 10 * 10. This is why there aren't 3*2 = 6 metallurgical/polarising magnifications stated as you might otherwise expect.Achromatic Objectives: 4X, 10X, 40X (S), 100X (S,OIL)So apparently the second row of objectives is not up to the task of being used with epi illumination (i.e., metallurgical use case, fair enough because epi illumination is certainly harder to design for than brightfield) or polarisation. And the first row can't do transmitted light, which seems strange to me (or perhaps they didn't want to list every permutation because it's rather tightly packed and silly looking: 40x, 50x, 80x, 100x....)

author: Chris Jones
author_rank: Regular Contributor
timestamp: March 21, 2015, 03:02:04 pm
content: Quote from: EEVblog on March 15, 2015, 12:55:10 amWhen I used to probe chips, we used a Karl Suss probe station with a Mitutoyo microscope on it.The microscope had 4 lenses that could be rotated into position depending on the magnification required. The highest one was a 100x objective. This is the lens (yes, $11k for one lens):http://www.edmundoptics.com.au/microscopy/infinity-corrected-objectives/mitutoyo-nir-nuv-uv-infinity-corrected-objectives/46409/The nice things about that lens are:1: can resolve tracks close to the wavelength of light2: Long enough working distance so you can get a probe needle in there to probe traces3: Lens can also focus UV, from the UV laser that was used for blasting windows through the protective glass covering the surface of the chip, to allow the probe needle to make contact.Actually for most things the 50x objective was better because you could see more stuff and the wavelength of light was probably the limitation so the 100x didn't give much better detail. I think the 50x lens was this one ($9k): (edited, was wrong link)http://www.edmundoptics.com.au/microscopy/infinity-corrected-objectives/mitutoyo-nir-nuv-uv-infinity-corrected-objectives/46408/Probably your best bet might be to find a surplus probe station at auction, for example lot 293 herehttps://www.netbid.com/kataloge/V13435_DE.pdf) I think they might be export controlled so you might need a licence.

author: Rupunzell
author_rank: Frequent Contributor
timestamp: March 22, 2015, 06:28:25 am
content: Quote from: rs20 on March 16, 2015, 09:52:27 amBright field, Dark field can be applied to both transmitted illumination (microscope lighting from the bottom) passing the translucent or semi translucent specimen then into the objective or Epi illumination. Epi means top or in this case, light from top.Beyond the microscope system, there are specimen preparation steps to allow microscopic imaging. Simply "putting the object" under a microscope often does not work all that well for a host of reasons.Bright field Epi illumination diagram. Note the various optical elements, iris related to the illumination path and observation light path.http://nanophys.kth.se/nanophys/facilities/nfl/nikon-me600/bf-epi.htmlDark field Epi illumination diagram:http://nanophys.kth.se/nanophys/facilities/nfl/nikon-me600/darkfield/darkfield-epi.htmlThe illumination system accounts for about 50% of the microscope's overall optical performance. In some cases, the illumination system is more important than the imaging optics. Overall optical microscope system requirements are highly dependent on specific needs for optimized image results.Bernice

author: EEVblog
author_rank: Unknown
timestamp: April 27, 2015, 01:12:59 pm
content: Resurrecting an old thread.Is this Nikon Metaphot worth a shot?http://www.ebay.com.au/itm/Nikon-Metaphot-Microscope-for-Metallurgy-Wafer-Inspection-Metahpot-/141576304516Light source should be easy enough to add, and can likely hack on a camera somehow.

author: SeanB
author_rank: Super Contributor
timestamp: April 27, 2015, 01:33:27 pm
content: Should fit with an adaptor. Make an offer, they will be killing you in postage.

author: Rupunzell
author_rank: Frequent Contributor
timestamp: April 27, 2015, 04:54:29 pm
content: Microscope light sources are often not simple. The good ones have a square filament bulb with a reflector that can be adjusted to focus the light for the condenser lens that also lives in the lamp house. It it is a halogen lamp, they often have a IR filter to reduce the amount of heat transferred into the microscope's optical system.Camera tube will need a relay lens for the specific imager and all the related mechanical bits.5x objective & 40x objective are the less often used for semi wafer work. The most common used is 10x, 20x and these are missing.BerniceQuote from: EEVblog on April 27, 2015, 01:12:59 pm