排序方式: 共有270条查询结果,搜索用时 221 毫秒
31.
32.
Channel temperature determination of a multifinger AlGaN/GaN high electron mobility transistor using a micro-Raman technique
下载免费PDF全文
![点击此处可从《中国物理 B》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Self-heating in a multifinger AlGaN/GaN high electron mobility transistor (HEMT) is investigated by micro-Raman spectroscopy. The device temperature is probed on the die as a function of applied bias. The operating temperature of the AlGaN/GaN HEMT is estimated from the calibration curve of a passively heated AlGaN/GaN structure. A linear increase of junction temperature is observed when direct current dissipated power is increased. When the power dissipation is 12.75 W at a drain voltage of 15 V, a peak temperature of 69.1°C is observed at the gate edge on the drain side of the central finger. The position of the highest temperature corresponds to the high-field region at the gate edge. 相似文献
33.
Analysis and finite element simulation of electromagnetic heating in the nitride MOCVD reactor
下载免费PDF全文
![点击此处可从《中国物理 B》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Electromagnetic field distribution in the vertical metal
organic chemical vapour deposition (MOCVD) reactor is simulated by
using the finite element method (FEM). The effects of alternating
current frequency, intensity, coil turn number and the distance
between the coil turns on the distribution of the Joule heat are
analysed separately, and their relations to the value of Joule heat
are also investigated. The temperature distribution on the
susceptor is also obtained. It is observed that the results of the
simulation are in good agreement with previous measurements. 相似文献
34.
Comparative study of different properties of GaN films grown on(0001) sapphire using high and low temperature AlN interlayers
下载免费PDF全文
![点击此处可从《中国物理 B》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Comparative study of high and low temperature AlN
interlayers and their roles in the properties of GaN epilayers
prepared by means of metal organic chemical vapour deposition on
(0001) plane sapphire substrates is carried out by high resolution
x-ray diffraction, photoluminescence and Raman spectroscopy. It is
found that the crystalline quality of GaN epilayers is improved
significantly by using the high temperature AlN interlayers, which
prevent the threading dislocations from extending, especially for
the edge type dislocation. The analysis results based on
photoluminescence and Raman measurements demonstrate that there
exist more compressive stress in GaN epilayers with high temperature
AlN interlayers. The band edge emission energy increases from
3.423~eV to 3.438~eV and the frequency of Raman shift of $E_{2
}$(TO) moves from 571.3~cm$^{ - 1}$ to 572.9~cm$^{ - 1}$ when the
temperature of AlN interlayers increases from 700~$^{\circ}$C to
1050~$^{\circ}$C. It is believed that the temperature of AlN
interlayers effectively determines the size, the density and the
coalescence rate of the islands, and the high temperature AlN
interlayers provide large size and low density islands for GaN
epilayer growth and the threading dislocations are bent and
interactive easily. Due to the threading dislocation reduction in
GaN epilayers with high temperature AlN interlayers, the approaches
of strain relaxation reduce drastically, and thus the compressive
stress in GaN epilayers with high temperature AlN interlayers is
high compared with that in GaN epilayers with low temperature AlN
interlayers. 相似文献
35.
Study on the drain bias effect on negative bias temperature instability degradation of an ultra-short p-channel metal-oxide-semiconductor field-effect transistor
下载免费PDF全文
![点击此处可从《中国物理 B》网站下载免费的PDF全文](/ch/ext_images/free.gif)
This paper studies the effect of drain bias on
ultra-short p-channel metal-oxide-semiconductor field-effect
transistor (PMOSFET) degradation during negative bias temperature
(NBT) stress. When a relatively large gate voltage is applied, the
degradation magnitude is much more than the drain voltage which is
the same as the gate voltage supplied, and the time exponent gets
larger than that of the NBT instability (NBTI). With decreasing
drain voltage, the degradation magnitude and the time exponent all
get smaller. At some values of the drain voltage, the degradation
magnitude is even smaller than that of NBTI, and when the drain
voltage gets small enough, the exhibition of degradation becomes
very similar to the NBTI degradation. When a relatively large drain
voltage is applied, with decreasing gate voltage, the
degradation magnitude gets smaller. However, the time exponent
becomes larger. With the help of electric field simulation, this
paper concludes that the degradation magnitude is determined by the
vertical electric field of the oxide, the amount of hot holes
generated by the strong channel lateral electric field at the
gate/drain overlap region, and the time exponent is mainly
controlled by localized damage caused by the lateral electric
field of the oxide in the gate/drain overlap region where hot carriers
are produced. 相似文献
36.
Fabrication and characterization of groove-gate MOSFETs based on a self-aligned CMOS process 总被引:2,自引:0,他引:2
下载免费PDF全文
![点击此处可从《中国物理》网站下载免费的PDF全文](/ch/ext_images/free.gif)
N and P-channel groove-gate MOSFETs based on a self-aligned CMOS process
have been fabricated and characterized. For the devices with channel length
of 140nm, the measured drain induced barrier lowering (DIBL) was 66mV/V for
n-MOSFETs and 82mV/V for p-MOSFETs. The substrate current of a groove-gate
n-MOSFET was 150 times less than that of a conventional planar n-MOSFET.
These results demonstrate that groove-gate MOSFETs have excellent
capabilities in suppressing short-channel effects. It is worth emphasizing
that our groove-gate MOSFET devices are fabricated by using a simple process
flow, with the potential of fabricating devices in the sub-100nm range. 相似文献
37.
Influence of dislocations in the GaN layer on the electrical properties of an AlGaN/GaN heterostructure
下载免费PDF全文
![点击此处可从《中国物理 B》网站下载免费的PDF全文](/ch/ext_images/free.gif)
This paper reports on a comparative study of the spatial
distributions of the electrical, optical, and structural properties
in an AlGaN/GaN heterostructure. Edge dislocation density in the GaN
template layer is shown to decrease in the regions of the wafer
where the heterostructure sheet resistance increases and the GaN
photoluminescence band-edge energy peak shifts to a high wavelength.
This phenomenon is found to be attributed to the local compressive
strain surrounding edge dislocation, which will generate a local
piezoelectric polarization field in the GaN layer in the opposite
direction to the piezoelectric polarization field in the AlGaN layer and
thus help to increase the two-dimensional electron gas
concentration. 相似文献
38.
Taking the actual operating condition of complementary metal oxide
semiconductor (CMOS) circuit into account, conventional direct
current (DC) stress study on negative bias temperature instability
(NBTI) neglects the detrapping of oxide positive charges and the
recovery of interface states under the `low' state of p-channel metal
oxide semiconductor field effect transistors (MOSFETs) inverter
operation. In this paper we have studied the degradation and recovery
of NBTI under alternating stress, and presented a possible recovery
mechanism. The three stages of recovery mechanism under positive bias
are fast recovery, slow recovery and recovery saturation. 相似文献
39.
A novel model for lightly-doped-drain (LDD) MOSFETs is proposed, which utilizes the empirical hyperbolic tangent function to describe the I-V characteristics. The model includes the strong inversion and subthreshold mechanism, and shows a good prediction for submicron LDD MOSFET. Moreover, the model requires low computation time consumption and is suitable for design of MOSFETs devices and circuits. 相似文献
40.
基于密度泛函理论的爬坡弹性带方法,对金红石相二氧化钛晶体中钛间隙、钛空位、氧间隙、氧空位4种本征缺陷的扩散特征进行了研究.对比4种本征缺陷在晶格内部沿不同扩散路径的过渡态势垒后发现,缺陷扩散过程呈现出明显的各向异性.其中,钛间隙和氧间隙沿[001]方向具有最小的扩散势垒路径,激活能分别为0.505 eV和0.859 eV;氧空位和钛空位的势垒最小的扩散路径分别沿[110]方向和[111]方向,激活能分别为0.735 eV和2.375 eV. 相似文献