微熱板陣列的熱干擾

針對微熱板陣列建立了熱路模型,并對熱干擾進行分析.結果表明,由于微熱板懸空結構的熱阻比硅芯片的熱阻高3個數量級,因此微熱板陣列芯片的熱干擾溫度取決于封裝對環境的熱阻,而芯片上器件的間距對熱干擾溫度的影響可以忽略.研制了3種布局、TO5和DIP16兩種封裝形式的微熱板陣列,并對陣列中的熱干擾問題進行了實驗測試.測試數據驗證了熱路模型的結論.因此,減小微熱板陣列或集成芯片的熱干擾的關鍵在于,盡可能增大微熱板懸空結構的熱阻以及選用熱阻小的封裝形式

基于非线性 PCA的微气体传感器阵列信号处理

在線性疊加模型基礎上提出了氣體傳感器對混合氣體的非線性疊加模型,并引入了非線性主成分分析(NonlinearPrincipalComponentAnalysis,NLPCA)法對微傳感器陣列的信號進行處理。使用該模型對由4個微熱板式氣體傳感器組成的陣列的信號進行了分析,對照基于線性疊加模型的主成分分析法(PrincipalComponentAnalysis,PCA)的識別結果,說明該方法能夠提高對混合氣體識別和量化的準確度。A nonlinear superposition model was proposed based on the common linear additive model the micro gas sensor array signal processing to improve the precision of quantification and identification. According to the nonlinear model, the Nonlinear Principal Component Analysis (NLPCA) was proposed to process the response signals obtained from a 4 Micro-hotplate (MHP) based gas sensor array. Com-pared with the analyzing results obtained from Principal Component Analysis (PCA), which bases on the linear additive model, the accuracy of gas component identification and concentration quantification are improved greatly

微气体传感器的稳定性测试研究

測試了一組微熱板式氣體傳感器的穩定性,著重討論了穩定性的幾種描述方法,采用統計學方法對文獻中常用于描述穩定性的幾種特征參數進行了比較和取舍,引入了特征參數離散度來描述氣體傳感器的穩定性,并使用該方法比較了預加熱時間對傳感器穩定性的影響。The stability of a series of micro hotplate based gas sensors were investigated and the descriptive methods were discussed in focus. From the point of statistics, the general feature parameters to denote gas sensors' stability were compared and an optimal parameter set was extracted. The variation coefficient of parameters was adopted to describe the stability. By using this approach, the influences of preheating time on gas sensors' stability were investigated

基于硅微加工工艺的微热板传热分析

針對常壓和真空兩種環境 ,通過三維有限元模擬分析了背面體硅加工型、正面體硅加工型和表面加工型三種微熱板 (MHP)的傳熱主渠道和加熱功率 .制作了背面體硅加工型和表面加工型MHP ,并對兩者在常壓及 13 3Pa氣壓下的加熱功率進行了測試 .實驗值與有限元分析結果一致 ,表明雖然真空中表面加工型MHP熱功耗小于背面體硅加工型MHP ,但薄層空氣導熱使表面加工型MHP在大氣中的功耗大幅增加 ,并大于背面體硅加工型MHP的熱功耗 .Thermal simulation of three types of MHPs (surface micro-machined, back-side bulk silicon micro-machined, and front-side bulk silicon micro-machined) working in atmosphere and vacuum is performed with 3D FEA. Their first two types of MHPs are fabricated and their experimental results are in agreement with the FEA. It is shown that, power consumption of the surface micromachined MHP is smaller than the back-side bulk silicon micromachined MHP in vacuum; however, in atmosphere, thermal conduction of the thin air layer in the surface micro-machined MHP dramatically increases its power consumption, with is much larger than that of the back-side bulk silicon micromachined MHP

气体传感器阵列信号的盲分离研究

Responses of a Micro-hotplate based integrated gas sensor array to CO and CH4 were measured with an automated gas sensor calibration system. Combining with the blind source separation(BSS techniques, the blind separability in gas mixture analysis was discussed. The widely used BSS approach-Independent Component Analysis(ICA) was adopted to verify the proposed method by analyzing the gas mixtures of CO and CH, The. analysis results demonstrate that BSS was an effective way to extract the information of gas components in mixtures, from which the gas concentrations can be estimated. The average relative quantification errors were 9.37\% and 8.11\% for CO and CH4, respectively, in the specified concentration ranges

Prediction of Energy Resolution in the JUNO Experiment

International audienceThis paper presents the energy resolution study in the JUNO experiment, incorporating the latest knowledge acquired during the detector construction phase. The determination of neutrino mass ordering in JUNO requires an exceptional energy resolution better than 3% at 1 MeV. To achieve this ambitious goal, significant efforts have been undertaken in the design and production of the key components of the JUNO detector. Various factors affecting the detection of inverse beta decay signals have an impact on the energy resolution, extending beyond the statistical fluctuations of the detected number of photons, such as the properties of liquid scintillator, performance of photomultiplier tubes, and the energy reconstruction algorithm. To account for these effects, a full JUNO simulation and reconstruction approach is employed. This enables the modeling of all relevant effects and the evaluation of associated inputs to accurately estimate the energy resolution. The study reveals an energy resolution of 2.95% at 1 MeV. Furthermore, the study assesses the contribution of major effects to the overall energy resolution budget. This analysis serves as a reference for interpreting future measurements of energy resolution during JUNO data taking. Moreover, it provides a guideline in comprehending the energy resolution characteristics of liquid scintillator-based detectors