A hot hole-programmed and low-temperature-formed SONOS flash memory

Abstract

In this study, a high-performance TixZrySizO flash memory is demonstrated using a sol–gel spin-coating method and formed under a low annealing temperature. The high-efficiency charge storage layer is formed by depositing a well-mixed solution of titanium tetrachloride, silicon tetrachloride, and zirconium tetrachloride, followed by 60 s of annealing at 600°C. The flash memory exhibits a noteworthy hot hole trapping characteristic and excellent electrical properties regarding memory window, program/erase speeds, and charge retention. At only 6-V operation, the program/erase speeds can be as fast as 120:5.2 μs with a 2-V shift, and the memory window can be up to 8 V. The retention times are extrapolated to 106 s with only 5% (at 85°C) and 10% (at 125°C) charge loss. The barrier height of the TixZrySizO film is demonstrated to be 1.15 eV for hole trapping, through the extraction of the Poole-Frenkel current. The excellent performance of the memory is attributed to high trapping sites of the low-temperature-annealed, high-κ sol–gel film.

Low power zinc-oxide based charge trapping memory with embedded silicon nanoparticles via poole-frenkel hole emission

“…[3][4][5] In 1938, Frenkel explained the increase of the carriers thermal emission rate in an external electric field by the barrier lowering associated with the Coulomb potential of the carriers: as the applied field increases, the barrier height decreases further, and due to this barrier lowering, the thermal emission rate of charges exponentially increases. 22,24,25 This effect has often been assigned to a donor trap, which is neutral when it contains an electron and is positively charged when the electron is absent so that a Coulombic attraction exists. In the ZnO memory described in this Letter, the ZnO …”

Tunnel field-effect transistor charge-trapping memory with steep subthreshold slope and large memory window

“…Charge-trapping memory shows higher scaling ability and reliability owing to the discrete traps present in the charge-trapping medium. [1][2][3][4][5][6][7][8][9][10][11] Therefore, charge-trapping memory devices have been developed worldwide. However, charge-trapping memory requires a much larger memory window and the increase of bit density per cell operation for lower-power operation and large memory capacity.…”

Low temperature below 200 °C solution processed tunable flash memory device without tunneling and blocking layer

“…Hence, the main challenge is to simultaneously achieve deep intrinsic charge traps together with very low leakage current at low processing temperatures. There are a few reports on solution processed flash memory by using polymer materials [29,30], but these devices degrade after only few cycles of operation in normal environmental conditions and they are not capable of working at higher temperatures.…”