Font Size: a A A

Monte Carlo Simulation Research Of Photon Irradiation On Phase Change Random Access Memory Cell

Posted on:2017-09-03Degree:MasterType:Thesis
Country:ChinaCandidate:Y F GuoFull Text:PDF
GTID:2348330509460347Subject:Microelectronics and Solid State Electronics
Abstract/Summary:PDF Full Text Request
As a new type of non-volatile memory device, phase change random access memory(PCRAM) is considered to be one of the most promising candidates to satisfy what the aerospace engineering need in next-generation memories due to its excellent comprehensive performance. So for the purpose of the further development of PCRAM in the aerospace, it is of great significance to study the specific irradiation process of X(?)-ray which is the main component of space radiation particles, and to analyse the effect on the performance of the phase change memory cell.So in this thesis, on the basis of the phase change memory cell which has a bottom-up model, the photon irradiation simulation system is built to study the relationship between the total photon fluence and the performance of the PCRAM cell. The main researches are as follows:First of all, according to the movement mechanism of ray in matter, the physical process of photon beam vertically into the phase change memory cell is analyzed in the macroscopic and microscopic way. The results show that the effect of 5kev photon is the greatest on the phase change memory cell, and that photon interacts with the phase change medium mainly in the way of photoelectric effect, without considering other modes of interaction.Secondly, the Monte Carlo method is used to track of the photons into the phase change memory cell. Keep a record of the impact location, scattering angle and energy loss for every photon and the secondary particle. The finite element method is used to solve the electric and heat conduction equation, and build the electric, thermal and resistance simulation module. Take advantage of nucleation-growth theory to solve the phase transition process. Build the phase simulation module. And then combine the above five modules effectively to build the photon irradiation simulation system of the phase change memory cell in matlab. The results show that when the storage cell is in static, the information stored in the cell with low resistance state upsets under the action of a certain amount of external irradiation photons. However, the storage cell with high resistance state has a strong ability to resist the photon irradiation. And when the storage cell is in dynamic, the cell at the beginning of crystallization has a strong ability to resist the photon irradiation, and with the development of the crystallization process, the ability of photon irradiation is weaker; The storage cell in the process of amorphization has a strong ability to resist the photon irradiation.Finally, the relationships between the photon fluence rate with a certain total fluence with the performance of the PCRAM cell are studied. It shows that the smaller fluence rate is, the smaller the impact on the phase change memory cell is.
Keywords/Search Tags:Phase change random access memory, Photons radiation, Simulation system, Monte Carlo method
PDF Full Text Request
Related items