Study of Readout Channel Signals from Electrical Probe Memory

Abstract

Electrical probe memory using phase-change materials (PCM) has been considered as one of the most promising candidates for the future archival storage market. This can be attributed to the use of nanoscale probe that allows for ultra-high density and PCMs that lead to ultra-fast write/read speed and ultra-small energy consumption. For above reasons, considerable research is devoted to researching the write performances of the electrical probe memory, while ignoring the detailed study on its readout performances. To address this issue, we investigated the impulse response and step response of the electrical probe memory with crystalline bit embedded inside the amorphous matrix, which are the key factors to the readout channel design. Additionally, the appropriate readout excitations and the resulting DC offset are also well-established in order to ensure the reliability of the readout performances. We also assess the tip offset interference that may have an adverse effect on resulting signals. The calculated channel impulse response signal is eventually mathematically modelled so as to understand the behavior of the readback channel in linear and non-linear sense based on Gaussian and Lorentzian approximations.