Who we are

ZeptoBars is a Russian based R&D company focused on microelectronics and high-tech.

We are working on our commercial, slightly unusual microelectronic product and on the weekends having fun dissolving microchips in boiling acid. We are also trying to reinvent dye lasers utilizing the most recent advances in micro- and optoelectronics.

November 17, 2014

Torex XC6206 - CMOS LDO : weekend die-shot

Torex XC6206 is a popular and really tiny CMOS LDO, especially if you compare it to older bipolar ones, which were magnitude larger. 250mA LDO in SOT-23 might be hard to believe at first.

Datasheet mentions "laser trimming" but we see voltage set via mask and 2 fuses for fine tuning. It is possible though that they have common values set in mask (like this 3.3V one) , and rare voltages laser trimmed.

Die size 500x356 µm, 500nm technology.



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November 10, 2014

DIP 10Mhz Quartz oscillator based on Seiko NPC HA5022A3 : weekend die-shot

Seiko NPC HA5022A3 contains internal load capacitors, oscillator with amplitude limiting (for reduced power consumption) and optional frequency divider.
Die size 976x770 µm.

Quartz crystal is mounted on springs - in order to reduce impact of vibration on oscillation stability and to make it's damage less likely:


There is an oscillator IC soldered on the ceramic PCB, as well as 0.01uF power supply decoupling cap. It seems we need to go deeper:

November 4, 2014
November 1, 2014

BFR93 - BJT RF transistor : weekend die-shot

BFR93 is a popular, BJT npn RF transistor.
Die size 265x264 µm. Transistor itself occupy only small part of the die - it is impractical to cut smaller die, it is already almost a silicon cube:



October 27, 2014

10Mhz Quartz SMD oscillator based on Seiko NPC SM5009 : weekend die-shot

Seiko NPC SM5009 contains internal load capacitors, oscillator with amplitude limiting (for reduced power consumption) and optional frequency divider.

Die size 1194x897 µm, 800nm technology.




October 20, 2014

OnSemi MMBT2222A - npn BJT transistor : weekend die-shot



Die size 343x343 µm. Comparing to NXP BC847B die area is 1.5x larger (0.118 vs 0.076mm²), but maximum continuous collector current is 6 times higher (600mA vs 100mA, SOT-23 in both cases). This huge increase in current per transistor area is achieved by shunting thin (=high-resistance) base layer with metal. High resistance of base layer is the limiting factor for maximum collector current in BC847B.
October 20, 2014

NXP 2N7002 N-channel MOSFET : weekend die-shot


Die size 377x377 µm.

Hexagonal cells of TrenchMOS transistor has 4µm size.