Trying to View an Active 555 with an Electron Microscope
Ben uses an electron microscope in an attempt to take a look at a 555 while it’s operating. He writes:
I used my DIY scanning electron microscope to view a 555 timer circuit while it was powered. The circuit is a simple oscillator with a very long time constant to make the changes easy to see. My plan was to view the silicon die itself, and hopefully discern changes in its internal circuitry as the oscillations occurred. As it turns out, I was only able to “see” the charge of the electrical wires going to the chip socket. There is likely a clear oxide layer that covers the silicon die, and needs to be removed with hydrofluoric acid in order to use the SEM to inspect the die itself while powered.
While he wasn’t successful this first time out, it was still pretty cool to see how he went about it, and learning the hazards of this kind of work. I look forward to seeing his next attempt!
Adafruit publishes a wide range of writing and video content, including interviews and reporting on the maker market and the wider technology world. Our standards page is intended as a guide to best practices that Adafruit uses, as well as an outline of the ethical standards Adafruit aspires to. While Adafruit is not an independent journalistic institution, Adafruit strives to be a fair, informative, and positive voice within the community – check it out here: adafruit.com/editorialstandards
Stop breadboarding and soldering – start making immediately! Adafruit’s Circuit Playground is jam-packed with LEDs, sensors, buttons, alligator clip pads and more. Build projects with Circuit Playground in a few minutes with the drag-and-drop MakeCode programming site, learn computer science using the CS Discoveries class on code.org, jump into CircuitPython to learn Python and hardware together, TinyGO, or even use the Arduino IDE. Circuit Playground Express is the newest and best Circuit Playground board, with support for CircuitPython, MakeCode, and Arduino. It has a powerful processor, 10 NeoPixels, mini speaker, InfraRed receive and transmit, two buttons, a switch, 14 alligator clip pads, and lots of sensors: capacitive touch, IR proximity, temperature, light, motion and sound. A whole wide world of electronics and coding is waiting for you, and it fits in the palm of your hand.
Have an amazing project to share? The Electronics Show and Tell is every Wednesday at 7pm ET! To join, head over to YouTube and check out the show’s live chat – we’ll post the link there.
Google -voltage contrast SEM-;… this is a common failure analysis lab technique. Using a standard SEM with a test socket for the device, and a low accelerating voltage (+/- 1 kv), the charge in the circuit provides the black/white contrast as charge moves through gates and registers…. this looks really cool in digital/memory ICs. I did a stint on a VC-SEM in a FA lab back in the ’80’s as a college co-op student.
A scanning tunneling- or some variant of an atomic force microscope would probably be better for observing changes as the circuit operates.
KA1OS: If you have access to either of those and you’d like to make a video, we’d love to post it! 🙂
Google -voltage contrast SEM-;… this is a common failure analysis lab technique. Using a standard SEM with a test socket for the device, and a low accelerating voltage (+/- 1 kv), the charge in the circuit provides the black/white contrast as charge moves through gates and registers…. this looks really cool in digital/memory ICs. I did a stint on a VC-SEM in a FA lab back in the ’80’s as a college co-op student.