NVM Memory Principles

X-FAB supports various memory principles covering Zener zaps, Poly fuses, Floating gates and SONOS architecture. Below the characteristics and typical use cases are described accompanied by schematic cross section images.

Zener Zaps

Technology independent zener diode device.

Write
- melting of pn-junction
- destroying the device

Erase
- impossible

Usage
- for trimming purposes

Poly Fuses

Write
- external programming voltage supplied via pad
- device resistance is increased

Erase
- no re-programming / erase possible

Usage
- for trimming purposes

Floating Gate

Programming
- Fowler-Nordheim Tunneling

Erase
- Fowler-Nordheim Tunneling

Usage
- for EE-Latches, EEPROM, CEEPROM

Floating Gate

Programming
- Hot carrier injection

Erase
- UV light (on wafer level)

Usage
- OTP, trimOTP

SONOS

Programming
- modified Fowler-Nordheim tunneling
- electrons stored inside the nitride

Erase
- direct Fowler-Nordheim tunneling
- remove electrons from the nitride

Usage
- for EEPROM, NVRAM, Flash

 
 
 
Zener Diode Device
 
 
Poly Fuse Device
 
 
Two Transistor Single Poly-Si Device
 
 
Two Transistor Single Poly-Si Device
 
 
SONOS Device