Microchips are so ubiquitous, it's easy to lose sight of how remarkable they actually are. Something as mundane as a thermostat or singing greeting card contains millions of microscopic structures created in one of the most remarkable manufacturing processes ever developed.
The current process has been evolving since around 1977, and works sort of like a projector. Lasers shine light through a mask, which is like the blueprint for the chip, and projects the mask onto light-sensitive chemicals painted onto a slab of silicon. The result is almost like exposing a photograph: The light transmits the image of the chip onto the silicon, where it can be etched directly into the metal. This process is called photolithography, and as it's become more advanced, transistors have gotten smaller, faster and more energy efficient.