Study of Front-Side Approach to Retrieve Stored Data in Non-Volatile Memory Devices Using Scanning Capacitance Microscopy

Data are stored as electrical charges in floating gates of the transistors in Non-Volatile Memory (NVM) devices. Reading back this stored data will help in understanding how memory is organized which is important in the digital forensics field. Sample preparation from back-side approach had been attempted and scanning capacitance microscopy (SCM) can be used to probe the charges stored in the floating gate transistors directly. However, it is challenging to attain a uniform surface across the memory device using mechanical polishing and also difficult to read back the full data. In this paper, front-side sample preparation will be discussed for data retrieval with SCM probing method. The application has been demonstrated on 8-bit microcontroller with 16 KB ISP flash memory and 512 bytes EEPROM.