555 IC teardown – microscopic view of 555 IC
Above photo shows the silicon die of the 555 through a microscope. On top of the silicon, a thin layer of metal connects different parts of the chip. This metal is clearly visible in the photo as yellowish-white traces and regions. Under the metal, a thin, glassy silicon dioxide layer provides insulation between the metal and the silicon, except where contact holes in the silicon dioxide allow the metal to connect to the silicon. At the edge of the chip, thin wires connect the metal pads to the chip’s external pins.
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