It's on the SoC package not the die, just like in phones.

Dunedan · on Nov 10, 2020

Thanks for pointing out. My bad.

Here is a picture of the SoC with the 16GB of DDR4 RAM: https://www.apple.com/v/mac/m1/a/images/overview/chip__fffqz...

And here is the picture which confused by and tricked me into thinking the OP talked about the RAM integrated into the CPU (although upon closer inspection that picture also seems to cover the whole SoC package): https://www.apple.com/v/mac/m1/a/images/overview/chip_memory...