Thermoelectric Effects on Amorphization Process of Blade-Type Phase Change Random Access Memory

(Digital Presentation) Finite Element Modeling of Thermoelectric Effects in Phase Change Memory Cells

“…where is the mass density, is the specific heat, is the temperature, is the time, is the thermal conductivity, 𝑉 is the electric potential, is the electric current density, is the Seebeck coefficient, 𝐻 represents the latent heat of phase change, and 𝜌 is the volume charge density. In earlier works (5,8,16,18), the following more common form of J was used,…”

“…During this fast and reversible switching, the cells experience extremely large thermal gradients (~ 50 K/nm) and high current densities (~ 50 MA/cm 2 ) which result in significant coupling between heat current and electrical current. Therefore, thermoelectric (TE) effect induced heating or cooling contributions in the bulk and at materials and solid-liquid interfaces become very significant during the device operation (5)(6)(7)(8). The direction of current flow determines the locations of heat release (heating) or absorption (cooling) due to TE effects and thereby impacts the energy requirements for reset-set operations (9).…”

Blade-type phase-change random access memory technology, challenge and prospect

“…In addition to the interfacial effects, the thermoelectric (TE) effects, arising from the strong coupling between heat and charge transport inside the blade-type PCRAM, also has an intensive impact on resulting temperature [20]. To more comprehensively understand the physical mechanisms of the blade-type PCRAM, two types of TE effects, i.e., Thomson heating inside the bulk PCM/TiN heater and Peltier heating at the PCM/TiN heater interface, were assessed by simulations [21]. It was instructive to note that Thomson heating inside the bulk PCM had a more remarkable effect on written power than Thomson heating inside the TiN heater and Peltier heating at the PCM/TiN heater interface, as reflected in Fig.…”