共查询到19条相似文献,搜索用时 46 毫秒
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在宽范围偏置条件下,测量了GaAlAs红外发光二极管(IRLED)的低频噪声,发现1/f噪声幅值与偏置电流If^γ的r次方成正比,在小电流区,r≈1。在大电流区r≈2。建立了一个GaAlAs IRLED的1/f噪声模型,得到与实验一致的定性结果。基于该模型的分析表明.低电流区GaAlAs IRLED的1/f噪声源于体陷阱对非平衡载流子俘获和发射导致的扩散电流涨落,高电流区的1/f噪声源于结空间电荷区附近氧化层陷阱对该处表面势的调制而引起载流子表面复合速率的涨落。该研究结果为1/厂噪声表征GaAlAs IRLED的可靠性提供了实验基础与理论依据。 相似文献
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提出了一种基于智能温控的RTS噪声测试与分析新方法。该方法利用高k栅介质SOI LDMOS边界陷阱特性,首先建立了含有俘获时间常数、发射时间常数以及噪声幅度等参数的RTS噪声模型;然后设计了RTS噪声智能温控测试系统;最后对实测RTS噪声数据进行频谱变换,得到噪声功率谱密度并作分析。实验表明,该测试系统可以有效地获取高k栅介质SOI LDMOS的RTS噪声,具有良好的动态特性,且其本底噪声抑制率较高,较待测信号低两个数量级左右。 相似文献
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在宽范围偏置条件下,测量了电应力前后GaAlAs红外发光二极管(IRED)的低频噪声,发现应力前后1/f噪声随偏置电流变化的规律没有改变,但应力后1/f噪声幅值比应力前增加大约i00倍。基于载流子数和迁移率涨落的理论分析表明,GaAlAs IRED的1/f噪声在小电流时反映体陷阱特征,大电流时反映激活区陷阱特征,1/f噪声的增加归因于电应力在器件有源区诱生的界面陷阱和表面陷阱,因而,1/f噪声可以用来探测电应力对该类器件有源区的潜在损伤。 相似文献
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在可靠性筛选中检测具有潜在损伤的器件一直是个难题.对GaA lAs红外发光二极管(IRLED)功率老化前后低频噪声的测量发现,1/f噪声幅值与偏置电流的γ次方成正比(小电流区γ=1,在大电流区γ≈2),且老化后1/f噪声幅值比老化前增大2个数量级.基于载流子数涨落和迁移率涨落机制建立了一个GaA lAs IR LED的1/f噪声模型,分析结果表明GaA lAs IR LED的1/f噪声在小电流时反映体陷阱特征,大电流时反映激活区陷阱特征,1/f噪声的增加归因于功率老化诱生的界面陷阱和表面陷阱,1/f噪声可以用来检测GaA lAs IR LED s的潜在缺陷. 相似文献
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在可靠性筛选中检测具有潜在损伤的器件一直是个难题。对GaAlAs红外发光二极管(IRLED)功率老化前后低频噪声的测量发现,1/f噪声幅值与偏置电流的γ次方成正比(小电流区γ≈1,在大电流区γ≈2),且老化后1/f噪声幅值比老化前增大2个数量级。基于载流子数涨落和迁移率涨落机制建立了一个GaAlAs IR LED的1/f噪声模型,分析结果表明GaAlAs IR LED的1/f噪声在小电流时反映体陷阱特征,大电流时反映激活区陷阱特征,l/f噪声的增加归因于功率老化诱生的界面陷阱和表面陷阱,1/f噪声可以用来检测GaAlAs IR LEDs的潜在缺陷/ 相似文献
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报道了一种大功率无衬底N-GaAlAs/P-GaAs:Si单异质结红光二极管的制造工艺和主要光电特性。该器在50mA工作电流下,输出功率典型值7.5mW,最大功率11mW。 相似文献
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设计了一种采用金属支架直接导热的大功率红外发光二极管封装结构.该封装结构通过增加芯片底部金属座的厚度和尺寸,有效改善了散热性能,降低了封装热阻.实验测量表明,大功率红外发光二极管峰值波长为850nm,发光束角10°,典型输入功率为0.5W,最大输入功率可以达到2W以上,最大电光转换效率可达37.82%,最大辐射功率达到415.25 mW.Abstract: Using metal framework for heat conduction,a new packaging structure for power infrared light-emitting diode (LED) is introduced.This structure improves the heat dissipation effectively by increasing the size and the thickness of the metal framework.Experiment results show that the peak wavelength of the infrared LED is 850 nm,with the beam angle of 10° The typical input power is 0.5 W,and the maximum input power can reach higher than 2 W.The largest electro-optical conversion efficiency is up to 37.82%,and the largest radiation power reaches 415.25 mW. 相似文献
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Low-frequency intensity noise displaying 1/f dependency of the light polarized parallel and perpendicular to the junction plane and the correlation between these noise components is investigated in GaAlAs diode lasers. The absolute noise level for the component polarized parallel to the junction (lasing component) rises about 40 dB as the current passes through lasing threshold, while the noise for the orthogonal polarization drops by about 5 dB. The two noise components are well correlated slightly below threshold (coherence function ∼ 0.9), but the coherence function drops rapidly to near zero above threshold. An exception to this behavior occurs in the lasing mode when mode hopping takes place, when the two noise components are well correlated. A qualitative explanation for these phenomena is based on the relation between spontaneous and stimulated emission rates and fluctuations in the intracavity carrier density. 相似文献
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A brief overview of recent issues concerning the low frequency (LF) noise in modern CMOS devices is given. The approaches such as the carrier number and the Hooge mobility fluctuations used for the analysis of the noise sources are presented and illustrated through experimental results obtained on advanced CMOS generations. The use of the LF noise measurements as a characterization tool of large area MOS devices is also discussed. The main physical features of random telegraph signals (RTSs) observed in small area MOS transistors are reviewed. The impact of scaling on the LF noise and RTS fluctuations in CMOS silicon devices is also addressed. Experimental results obtained on 0.18 μm CMOS technologies are used to predicting the trends for the noise figure of foregoing CMOS technologies e.g. 0.1 μm and beyond. The formulation of the thermal noise underlying the LF fluctuations in MOSFETs is recalled for completeness. 相似文献
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The FM-noise spectrum of index-guided GaAlAs-diode lasers is measured for different lengths of the laser cavity. The observed FM-noise peak near the internal laser resonance and the decrease of the FM noise with increasing cavity length is in agreement with a model which is considering the spontaneous emission noise source. From the measured noise data, the linewidth enhancement factor is determined. 相似文献
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In this paper, we report a comprehensive study of Random Telegraph Signal (RTS) noise in SiGe epitaxial base bipolar transistors. We analyse the multilevel fluctuations of base and emitter forward currents before and after reverse stress on the emitter-base junction. We show the influence of the chemical treatment preceeding polysilicon emitter deposition on noise properties. We identified that RTS noise arises from different regions in the device : the silicon/polysilicon interface if an oxidizing surface preparation is used, and the emitter periphery after stress-induced degradation. Temperature and bias dependent measurements allowed us to characterize these defects (activation energy, defect type), to analyse their impact to the low frequency noise properties of these transistors and to discuss the role of hot carrier stressing. 相似文献
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The nature of the output intensity fluctuation noise generated when semiconductor lasers are irradiated by their own output beam are described. A possible explanation of their generation mechanism is presented utilising a simple rate equation model with an additional term accounting for the multiple reflections of the laser beam. 相似文献
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The Random Telegraph Signal (RTS) noise amplitude in Silicon-on-Insulator MOSFETs is studied as a function of the gate length, by adding a second transistor in series. Different types of behavior can be distinguished, pointing toward a different origin of the related trapping centers. It is shown that in linear operation, the RTS amplitude and the corresponding low-frequency noise peak magnitude normally scales with 1/L. However, an increase with device length can also be found when the noise peaks of two RTSs add up. For RTSs occurring in the saturation regime, a complete elimination is observed for larger Ls, in support of the supposed film-related origin 相似文献
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The coherence length of two types of GaAlAs broad-band sources have been measured as a function of current. The noise properties of these devices were also measured in short path-length difference interferometers. 相似文献
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A method for measuring the noise parameters of MESFETs and HEMTs is presented. It is based on the fact that three independent noise parameters are sufficient to fully describe the device noise performance. It is shown that two noise parameters, R n and |Y OPT|, can be directly obtained from the frequency variation of the noise figure F 50 corresponding to a 50 Ω generator impedance. By using a theoretical relation between the intrinsic noise sources as additional data, the F 50 measurement only can provide the four noise parameters. A good agreement with more conventional techniques is obtained 相似文献
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Jianjun Gao 《Solid-state electronics》2011,63(1):42-48
A new method for the determination of the four noise parameters of the metal oxide semiconductor field effect transistors (MOSFETs) based on the noise figure measurement system without microwave tuner is presented. The noise parameters are determined based on a set of analytical expressions of noise parameters by fitting the measured noise figure of the active device. These expressions are derived from an accurate small signal and noise equivalent circuit model, which takes into account the substrate parasitics, pad capacitances, and series inductances. On-wafer experimental verification is presented and a comparison with tuner based method is given. Good agreement is obtained between simulated and measured results for 0.5 × 5 × 16 μm, 0.35 × 5 × 16 μm and 0.18 × 5 × 16 μm (gate length × number of gate fingers × unit gate width) MOSFETs. 相似文献