🏛️國立陽明交通大學機構典藏

Search Results

Now showing 1 - 4 of 4

A Comprehensive Characterization Method for Lateral Profiling of Interface Traps and Trapped Charges in P-SONOS Cell Devices
(2017-03)
Guo, Jyh-Chyurn
;
Du, Pei-Ying
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
A comprehensive characterization method has been developed in this paper for reliable lateral profiling of the interface traps (Delta N-it), localized charges (Delta N-ot), and trapped holes (Delta N-hole) in P-SONOS cell devices. Charge pumping current (I-CP) measurement can be used to probe Delta N-it and Delta N-ot from the increase of maximum I-CP (I-CP,I- max) and the shift of I-CP curve along the base level voltage (V-b). When increasing the program and erase (P/E) cycles, the negative threshold voltage (V-T) shift at both program and erase states suggests the generation of Delta N-hole. The evolution of Delta N-it, Delta N-ot, and Delta N-hole during P/E cycling can consistently explain the nonmonotonic variations of gate induced drain leakage current (I-GIDL) and substrate current (I-SUB) as well as dramatic differences between the source and drain. The lateral migration of Delta N-ot caused by extending P/E cycles may lead to the failure of two-bit operation in SONOS cell devices. The larger V-T shift and subthreshold swing, smaller read current, and lower transconductance may degrade the endurance and retention of P-SONOS when applied in Flash memory.
STUDY OF GATE-INJECTION OPERATED SONOS-TYPE DEVICES USING THE GATE-SENSING AND CHANNEL-SENSING (GSCS) METHOD
(2009)
Du, Pei-Ying
;
Lue, Hang-Ting
;
Wang, Szu-Yu
;
Huang, Tiao-Yuan
;
Hsieh, Kuang-Yeu
SONOS devices using gate injection programming and erasing have better cycling endurance because the gate oxide is not stressed by PIE operations. This work studies the gate injection behavior in detail using the recently developed gate-sensing and channel-sensing (GSCS) technique. GSCS accurately locates the charge centroid during programming/erasing and reliability tests. For the first time, we can track the charge centroid for gate-injection "top BE-SONOS" and various SONOS-type devices. Our results indicate that the charge centroid after electron gate injection is close to the nitride center, irrespective of various nitride thickness and top dielectric. Moreover, there is electron and hole vertical mismatch after hole gate injection. Comparing the results from SONS, we can clearly prove that electrons are mainly distributed inside the bulk nitride instead of the interfaces between oxide and nitride. For SNOS and SNS, where there is electron and hole injection simultaneously, two-region approximation can give us more detailed information about electron and hole capture. By comparing experimental data with theoretical modeling, we have shown that nitride 7nm or thicker captures all the injected electrons up to total charge area density similar to 10(13)cm(-2).
A study of gate-sensing and channel-sensing (GSCS) transient analysis method - Part II: Study of the intra-nitride behaviors and reliability of SONOS-type devices
(2008-08-01)
Du, Pei-Ying
;
Lue, Hang-Ting
;
Wang, Szu-Yu
;
Huang, Tiao-Yuan
;
Hsieh, Kuang-Yeu
For the first time, we can directly investigate the charge transport and intra-nitride behaviors of SONOS-type devices by exploiting the gate-sensing and channel-sensing (GSCS) method. Our results clearly indicate that for electron injection (+FN program), the electron centroid migrates from the bottom toward the nitride center, whereas for hole injection (-FN erase), holes first recombine with the bottom electrons and then gradually move upward. For the electron de-trapping processes under -V(G) stressing, the trapped electrons de-trap first from the bottom portion of nitride. We also develop a method to distinguish the electron de-trapping and hole injection erasing methods by comparing the erasing current density (J) versus the bottom oxide electric field (E). At short-term high-temperature baking, the electrons move from the top portion toward the bottom portion, and this intra-nitride transport becomes more significant for a thicker nitride. On the other hand, after long-term baking, the charge loss mainly comes from the bottom portion of nitride.
Pulse-IV Characterization of Charge-Transient Behavior of SONOS-Type Devices With or Without a Thin Tunnel Oxide
(2009-04-01)
Du, Pei-Ying
;
Lue, Hang-Ting
;
Wang, Szu-Yu
;
Huang, Tiaci-Yuan
;
Hsieh, Kuang-Yeu
The transient behavior of SONOS-type devices was investigated for the first time using pulse-IV technique. Three kinds of SONOS devices are studied: SONS (without top oxide), SONoS (with a thin top oxide), and SoNOS (with a thin bottom oxide). Devices with or without a thin tunnel oxide were able to provide very fast charge injection/detrapping, but their charge-transient behavior cannot be accurately monitored by conventional DC-IV method. By using specific pulse-IV setup for memory, we can measure the drain current response immediately after programming and erasing, as well as the fast charge relaxation under various reliability tests. The program and erase transient behavior shows that all devices are easily programmed and erased within 1 mu s at low gate voltages (< 6 V). Moreover, SONS shows the fastest program and erase speeds because of the absence of tunnel oxide, and silicon nitride has very low barrier height that offers fast injection. We have also examined the charge relaxation under various field and temperature conditions and found that the charge loss mainly came from external charge injection during retention, not from detrapping through thermionic emission.

學術出版;;Publications

Browse

Filters

Settings

Sort By

Results per page

🏛️國立陽明交通大學機構典藏

Search Results