February 21, 2013
Part II: How to «open» microchip and what's inside? Z80, Multiclet, MSP430, PIC and more
In this article we'll continue cracking microchips open. If you've missed first article - it's here.«Canonical» way of opening microchips:
Cut a small hole in the center of the chip with a dremel:WARNING!: All operations with acids must be performed in a fume hood, with proper protection (gloves, gas mask, e.t.c).
Put a droplet of fuming nitric or sulfuric acid there, heat up to ~100 ºC (~212 ºF). It is critical to use fuming acids - just concentrated (98% sulfuric or 70% nitric) won't cut it. After reaction ends - rinse with acetone, dry and put next droplet.
As a result we are getting exposed die, with all bond wires intact. The microchip still works - this might be useful if we want to probe it or modify eeprom data with UV laser.
What's inside
K565RU5 (pin-compatible to 4164 DRAM chip) - 64 Kib DRAM chip, heart of most of amateur computers made in late soviet times and early 90's. There was also RU7 chip (256 Kib) but it was hard to buy.Z80A - legendary successor of Intel 8080.
This is a photo of one of it's many clones. This one is likely made in DDR by MME company.
Die size - 4950x4720 µm, technology node - 5µm.
KR580VM80A just like KR580IK80A is an Intel 8080-compatible processor, which was in mass manufacturing in USSR until late 90's. Compared to KR580IK80A - die size is 20% smaller, IO peripherals are reworked.
Die size - 4634x4164 µm, 5µm technology.
MSP430F122 - 16-bit microcontroller made by Texas Instruments. What's interesting is that die is marked as MSP430F123, with larger flash size.
PIC12C508 - one of the "old" PIC's. Manufacturing technology - 1200nm, the oldest we've seen in microcontrollers being sold at the moment.
PIC16C505 - another "old" PIC, again 1200nm.
New RFID MIFARE chip from Moscow's metro - for several years Sitronics-Микрон was apparently using NXP RFID chips in Moscow's metro, but since February 2013 - we were finally able to find russian-made chips. New chip compared to NXP's one is 20% smaller, but not readable by NFC-readers in modern cell phones (might be a software issue). 180nm technology, aluminum metalization.
After metalization etch - it is clear that significant part of the chip is occupied by passive components (capacitors), and places under pads are empty.
Dual timer 556 - one of the oldest chips still being manufactured.
1886VE10 - Russian rad-hard 50Mhz microcontroller designed by Milandr and manufactured by Sitronics-Mikron on 180nm bulk-silicon technology. Radiation hardening is achieved by using edge-less transistors and 8T SRAM cells.
After metalization etch:
Not much to see in optical microscope:
Much better via scanning electron microscope:
These bright cilinders - are tungsten via's left after metalization etch. This is an image from electron microprobing - sample is being bombarded by electron beam and X-Ray spectra is analyzed.
STM32 STM32F103VGT6 - one of the largest STMicroelectronics microcontrollers on Cortex-M3 core.
1Mb of flash memory and 96kb of SRAM occupies it's enormous 5339x5188 µm die.
180nm SRAM is not really visible in optical microscope:
And again, electron microscope would help us:
Multiclet MCp0411100101 - basically is a superscalar out-of-order processor(4-wide at the moment) designed in Russia. 100Mhz clock, 180nm manufacturing technology.
Die size - 10.2x10.2 мм.
After metalization etch: (Warning, high-resolution image might kill your browser)
Area of SRAM cell- 21.28 µm2. Hence, each of 16 memory blocks has 72 Kibit of RAM. Obviously, ECC codes are used(72,64). Total accessible memory is 128 KiB.
Logo's:
Also, testing areas were cut along with the crystal, for example here is critical dimension test :
Hopefully that was interesting - follow us on Twitter @Zeptobars or subscribe to our RSS feed - we'll continue opening chips.