共查询到20条相似文献,搜索用时 171 毫秒
1.
Hot-carrier degradation for 90 nm gate length lightly-doped drain (LDD) NMOSFET with ultra-thin (1.4 nm) gate oxide is investigated under the low gate voltage stress (LGVS) and peak substrate current (Isub max) stress. It is found that the degradation of device parameters exhibits saturating time dependence under the two stresses. We concentrate on the effect of these two stresses on gate-induced-drain leakage (GIDL) current and stress induced leakage current (SILC). The characteristics of the GIDL current are used to analyse the damage generated in the gate-to-LDD region during the two stresses. However, the damage generated during the LGVS shows different characteristics from that during Isub stress. SILC is also investigated under the two stresses. It is found experimentally that there is a linear correlation between the degradation of SILC and that of threshold voltage during the two stresses. It is concluded that the mechanism of SILC is due to the combined effect of oxide charge trapping and interface traps for the ultra-short gate length and ultra-thin gate oxide LDD NMOSFETs under the two stresses. 相似文献
2.
HU Shi-Gang CAO Yan-Rong HAO Yue MA Xiao-Hua CHEN Chi WU Xiao-Feng ZHOU Qing-Jun 《中国物理快报》2008,25(11):4109-4112
Degradation of device under substrate hot-electron (SHE) and constant voltage direct-tunnelling (CVDT)stresses are studied using NMOSFET with 1.4- nm gate oxides. The degradation of device parameters and the degradation of the stress induced leakage current (SILC) under these two stresses are reported. The emphasis of this paper is on SILC and breakdown of ultra-thin-gate-oxide under these two stresses. SILC increases with stress time and several soft breakdown events occur during direct-tunnelling (DT) stress. During SHE stress, SILC firstly decreases with stress time and suddenly jumps to a high level, and no soft breakdown event is observed. For DT injection, the positive hole trapped in the oxide and hole direct-tunnelling play important roles in the breakdown. For SHE injection, it is because injected hot electrons accelerate the formation of defects and these defects formed by hot electrons induce breakdown. 相似文献
3.
Jinghao Zhao Hang Zhou Jiangwei Cui Qiwen Zheng Ying Wei Shanxue Xi 《辐射效应与固体损伤》2013,168(7-8):606-616
ABSTRACTThe authors perform gamma ray irradiation and hot carrier stress on RH H-Gate PD (partially depleted) SOI NMOSFETs as the experimental group and commercial strip-shaped gate PD SOI NMOSFETs as the control group. They analyse HCI degradation in samples and conclude that radiation could enhance HCI degradation in RH H-gate samples. Moreover, the mechanism is explained as the coupling effect between the front gate and back gate caused by TID radiation-induced trap charges in the buried oxide. 相似文献
4.
Negative bias temperature instability (NBTI) and stress-induced leakage current (SILC) both are more serious due to the aggressive scaling lowering of devices. We investigate the SILC during NBTI stress in PMOSFETs with ultra-thin gate dielectrics. The SILC sensed range from -1 V to 1 V is divided into four parts: the on-state SILC, the near-zero SILC, the off-state SILC sensed at lower positive voltages and the one sensed at higher positive voltages. We develop a model of tunnelling assisted by interface states and oxide bulk traps to explain the four different parts of SILC during NBTI stress. 相似文献
5.
A gate-last process for fabricating HfSiON/TaN n-channel metal-oxide-semiconductor-field-effect transistors(NMOSFETs)is presented.In the process,a HfSiON gate dielectric with an equivalent oxide thickness of 10 A was prepared by a simple physical vapor deposition method.Poly-Si was deposited on the HfSiON gate dielectric as a dummy gate.After the source/drain formation,the poly-Si dummy gate was removed by tetramethylammonium hydroxide(TMAH)wet-etching and replaced by a TaN metal gate.Because the metal gate was formed after the ion-implant doping activation process,the effects of the high temperature process on the metal gate were avoided.The fabricated device exhibits good electrical characteristics,including good driving ability and excellent sub-threshold characteristics.The device’s gate length is 73 nm,the driving current is 117μA/μm under power supply voltages of VGS=VDS=1.5 V and the off-state current is only 4.4 nA/μm.The lower effective work function of TaN on HfSiON gives the device a suitable threshold voltage(~0.24 V)for high performance NMOSFETs.The device’s excellent performance indicates that this novel gate-last process is practical for fabricating high performance MOSFETs. 相似文献
6.
The conduction mechanism of stress induced leakage current through ultra-thin gate oxide under constant voltage stresses 总被引:1,自引:0,他引:1 下载免费PDF全文
The conduction mechanism of stress induced leakage current (SILC) through 2nm gate oxide is studied over a gate voltage range between 1.7V and stress voltage under constant voltage stress (CVS). The simulation results show that the SILC is formed by trap-assisted tunnelling (TAT) process which is dominated by oxide traps induced by high field stresses. Their energy levels obtained by this work are approximately 1.9eV from the oxide conduction band, and the traps are believed to be the oxygen-related donor-like defects induced by high field stresses. The dependence of the trap density on stress time and oxide electric field is also investigated. 相似文献
7.
空间科学的进步对航天用电子器件提出了更高的性能需求, 绝缘体上硅(SOI)技术由此进入空间科学领域, 这使得器件的应用面临深空辐射环境与地面常规可靠性的双重挑战. 进行SOI N型金属氧化物半导体场效应晶体管电离辐射损伤对热载流子可靠性的影响研究, 有助于对SOI器件空间应用的综合可靠性进行评估. 通过预辐照和未辐照、不同沟道宽长比的器件热载流子试验结果对比, 发现总剂量损伤导致热载流子损伤增强效应, 机理分析表明该效应是STI辐射感生电场增强沟道电子空穴碰撞电离率所引起. 与未辐照器件相比, 预辐照器件在热载流子试验中的衬底电流明显增大, 器件的转移特性曲线、输出特性曲线、跨导特性曲线以及关键电学参数VT, GMmax, IDSAT退化较多. 本文还对宽沟道器件测试中衬底电流减小以及不连续这一特殊现象进行了讨论. 相似文献
8.
Hot-carrier degradation for 90nm gate length LDD-NMOSFET with ultra-thin gate oxide under low gate voltage stress 下载免费PDF全文
The hot-carrier degradation for 90~nm gate length lightly-doped drain
(LDD) NMOSFET with ultra-thin (1.4~nm) gate oxide under the low gate
voltage (LGV) (at Vg=Vth, where Vth is the
threshold voltage) stress has been investigated. It is found that the
drain current decreases and the threshold voltage increases after the
LGV (Vg=Vth stress. The results are opposite to the
degradation phenomena of conventional NMOSFET for the case of this
stress. By analysing the gate-induced drain leakage (GIDL) current
before and after stresses, it is confirmed that under the LGV stress
in ultra-short gate LDD-NMOSFET with ultra-thin gate oxide, the hot
holes are trapped at interface in the LDD region and cannot shorten
the channel to mask the influence of interface states as those in
conventional
NMOSFET do, which leads to the different degradation phenomena from those of the
conventional NMOS devices. This paper also discusses the degradation in the
90~nm gate length LDD-NMOSFET with 1.4~nm gate oxide under the LGV stress at
Vg=Vth with various drain biases. Experimental results show that
the degradation slopes (n) range from 0.21 to 0.41. The value of
n is
less than that of conventional MOSFET (0.5-0.6) and also that of the long gate
length LDD MOSFET (\sim0.8). 相似文献
9.
Degradation characteristics of PMOSFETs under negative bias
temperature--positive bias temperature--negative bias temperature
(NBT--PBT--NBT) stress conditions are investigated in this paper. It
is found that for all device parameters, the threshold voltage has
the largest shift under the first NBT stress condition. When the
polarity of gate voltage is changed to positive, the shift of device
parameters can be greatly recovered. However, this recovery is
unstable. The more severe degradation appears soon after
reapplication of NBT stress condition. The second NBT stress causes
in linear drain current to degrade greatly, which is different from
that of the first NBT stress. This more severe parameter shift
results from the wear out of silicon substrate and oxide interface
during the first NBT and PBT stress due to carrier
trapping/detrapping and hydrogen related species diffusion. 相似文献
10.
11.
研究了90nm工艺下栅氧化层厚度为1.4nm的n-MOSFET的击穿特性,包括V-ramp(斜坡电压)应力下器件栅电流模型和CVS(恒定电压应力)下的TDDB(经时击穿)特性,分析了电压应力下器件的失效和退化机理.发现器件的栅电流不是由单一的隧穿引起,同时还有电子的翻越和渗透.在电压应力下,SiO2中形成的缺陷不仅降低了SiO2的势垒高度,而且等效减小了SiO2的厚度(势垒宽度).另外,每一个缺陷都会形成一个导电通道,这些导电通道的形成增大了栅电流,导致器件性能的退化,同时栅击穿时间变长.
关键词:
超薄栅氧化层
斜坡电压
经时击穿
渗透 相似文献
12.
The NBTI degradation phenomenon and the role of hydrogen during NBT stress
are presented in this paper. It is found that PBT stress can recover a
fraction of Vth shift induced by NBTI. However, this recovery is
unstable. The original degradation reappears soon after reapplication of the NBT
stress condition. Hydrogen-related species play a key role during a device's NBT
degradation. Experimental results show that the diffusion species are
neutral, they repassivate Si dangling bond which is independent of the gate
voltage polarity. In addition to the diffusion towards gate oxide, hydrogen
diffusion to Si-substrate must be taken into account for it also has
important influence on device degradation during NBT stress. 相似文献
13.
采用不同的高场应力和栅应力对AlGaN/GaN HEMT器件进行直流应力测试,实验发现:应力后器件主要参数如饱和漏电流,跨导峰值和阈值电压等均发生了明显退化,而且这些退化还是可以完全恢复的;高场应力下,器件特性的退化随高场应力偏置电压的增加和应力时间的累积而增大;对于不同的栅应力,相对来说,脉冲栅应力和开态栅应力下器件特性的退化比关态栅应力下的退化大.对不同应力前后器件饱和漏电流,跨导峰值和阈值电压的分析表明,AlGaN势垒层陷阱俘获沟道热电子以及栅极电子在栅漏间电场的作用下填充虚栅中的表面态是这些不同应
关键词:
AlGaN/GaN HEMT器件
表面态(虚栅)
势垒层陷阱
应力 相似文献
14.
Effect of substrate bias on negative bias temperature instability of ultra-deep sub-micro p-channel metal--oxide--semiconductor field-effect transistors 下载免费PDF全文
The effect of substrate bias on the degradation during applying a
negative bias temperature (NBT) stress is studied in this paper.
With a smaller gate voltage stress applied, the degradation of
negative bias temperature instability (NBTI) is enhanced, and there
comes forth an inflexion point. The degradation pace turns larger
when the substrate bias is higher than the inflexion point. The
substrate hot holes can be injected into oxide and generate
additional oxide traps, inducing an inflexion phenomenon. When a
constant substrate bias stress is applied, as the gate voltage
stress increases, an inflexion comes into being also. The higher
gate voltage causes the electrons to tunnel into the substrate from
the poly, thereby generating the electron--hole pairs by impact
ionization. The holes generated by impact ionization and the holes
from the substrate all can be accelerated to high energies by the
substrate bias. More additional oxide traps can be produced, and
correspondingly, the degradation is strengthened by the substrate
bias. The results of the alternate stress experiment show that the
interface traps generated by the hot holes cannot be annealed, which
is different from those generated by common holes. 相似文献
15.
随着场效应晶体管(MOSFET)器件尺寸的进一步缩小和器件新结构的引入, 学术界和工业界对器件中热载流子注入(hot carrier injections, HCI)所引起的可靠性问题日益关注. 本文研究了超短沟道长度(L=30–150 nm)绝缘层上硅(silicon on insulator, SOI)场效应晶体管在HCI应力下的电学性能退化机理. 研究结果表明, 在超短沟道情况下, HCI 应力导致的退化随着沟道长度变小而减轻. 通过研究不同栅长器件的恢复特性可以看出, 该现象是由于随着沟道长度的减小, HCI应力下偏压温度不稳定性效应所占比例变大而导致的. 此外, 本文关于SOI器件中HCI应力导致的退化和器件栅长关系的结果与最近报道的鳍式场效晶体管(FinFET)中的结果相反. 因此, 在超短沟道情况下, SOI平面MOSFET器件有可能具有比FinFET器件更好的HCI可靠性. 相似文献
16.
Shu Tong Chang Wei-Ching Wang Shu-Hui Liao Chung-Yi Lin 《Applied Surface Science》2008,254(19):6177-6181
The stress distribution in the Si channel regions of a SiC source/drain and stressed silicon nitride liner NMOSFETs with various widths were studied using 3D simulations. The mobility enhancement was found to be dominated by the tensile stress along the transport direction. Stress along the width direction was found to have the least effect on the drain current. The compressive stress along the vertical direction perpendicular to the gate oxide (Szz) contributes significantly to the mobility enhancement and cannot be neglected in NMOSFETs with a width between 0.05 and 1 μm. The impact of width on performance improvements such as the drive current gain was also analyzed. 相似文献
17.
Decoupled-Plasma Nitridation (DPN) process with high level of nitrogen incorporation is widely used in the state-of-the-art technology, in order to reduce gate leakage current and boron penetration. However, due to the low temperature DPN process, the post-nitridation annealing treatment is required to improve the ultra-thin gate oxide integrity. In this paper, the effect of post-nitridation annealing on DPN ultra-thin gate oxide was investigated. The device performance and reliability were evaluated in three different post-nitridation annealing ambient (N2/O2, He, and NO). 相似文献
18.
对0.18 μm互补金属氧化物半导体(CMOS)工艺的N型金属氧化物半导体场效应晶体管(NMOSFET)及静态随机存储器(SRAM)开展了不同剂量率下的电离总剂量辐照试验研究. 结果表明: 在相同累积剂量, SRAM的低剂量率辐照损伤要略大于高剂量率辐照的损伤, 并且低剂量率辐照损伤要远大于高剂量率辐照加与低剂量率辐照时间相同的室温退火后的损伤. 虽然NMOSFET 低剂量率辐照损伤略小于高剂量率辐照损伤, 但室温退火后, 高剂量率辐照损伤同样要远小于低剂量率辐照损伤. 研究结果表明0.18 μm CMOS工艺器件的辐射损伤不是时间相关效应. 利用数值模拟的方法提出了解释CMOS器件剂量率效应的理论模型. 相似文献
19.
《中国物理 B》2021,30(7):77305-077305
The performance degradation of gate-recessed metal–oxide–semiconductor high electron mobility transistor(MOSHEMT) is compared with that of conventional high electron mobility transistor(HEMT) under direct current(DC) stress,and the degradation mechanism is studied. Under the channel hot electron injection stress, the degradation of gate-recessed MOS-HEMT is more serious than that of conventional HEMT devices due to the combined effect of traps in the barrier layer, and that under the gate dielectric of the device. The threshold voltage of conventional HEMT shows a reduction under the gate electron injection stress, which is caused by the barrier layer traps trapping the injected electrons and releasing them into the channel. However, because of defects under gate dielectrics which can trap the electrons injected from gate and deplete part of the channel, the threshold voltage of gate-recessed MOS-HEMT first increases and then decreases as the conventional HEMT. The saturation phenomenon of threshold voltage degradation under high field stress verifies the existence of threshold voltage reduction effect caused by gate electron injection. 相似文献
20.
对超深亚微米PMOS器件的负栅压温度不稳定性(NBTI)退化机理进行了研究.主要集中在对器件施加NBT和随后的PBT应力后器件阈值电压的漂移上.实验证明反型沟道中空穴在栅氧中的俘获以及氢分子在栅氧中的扩散是引起NBTI退化的主要原因.当应力条件变为PBT时,陷落的空穴可以快速退陷,但只有部分氢分子可以扩散回栅氧与衬底界面钝化硅悬挂键,这就导致了PBT条件下阈值电压只能部分恢复.
关键词:
超深亚微米PMOS器件
负偏压温度不稳定性
界面陷阱
氢气 相似文献