Etching mask optimization of InAs/GaSb superlattice mid-wavelength infared 640×512 focal plane array

In this paper we focused on the mask technology of inductively coupled plasma（ICP） etching for the mesa fabrication of infrared focal plane arrays（FPA）.By using the SiO_2 mask,the mesa has higher graphics transfer accuracy and creates less micro-ripples in sidewalls.Comparing the IV characterization of detectors by using two different masks,the detector using the SiO_2 hard mask has the R_0A of 9.7×10~6 Ω·cm^2,while the detector using the photoresist mask has the R_0A of3.2 × 10~2 Ω·cm^2 in 77 K.After that we focused on the method of removing the remaining SiO_2 after mesa etching.The dry ICP etching and chemical buffer oxide etcher（BOE） based on HF and NH4 F are used in this part.Detectors using BOE only have closer R_0A to that using the combining method,but it leads to gaps on mesas because of the corrosion on AlSb layer by BOE.We finally choose the combining method and fabricated the 640×512 FPA.The FPA with cutoff wavelength of 4.8 μm has the average R_0A of 6.13 × 10~9 Ω·cm^2 and the average detectivity of 4.51 × 10~9 cm·Hz^（1/2）.W^（-1）at 77 K.The FPA has good uniformity with the bad dots rate of 1.21%and the noise equivalent temperature difference（NEDT） of 22.9 mK operating at 77 K.

Hydrocarbon generation mechanism of lamalginite- and telalginite-dominated source rocks in a saline lake basin: A case study of the Permian Lucaogou formation in the Jimusaer Sag, Junggar Basin

The hydrocarbon generation of source rocks is significantly influenced by organic matter type, chemical element composition, and structural characteristics of kerogen. We classified the organic matter types in the shale of the Lucaogou Formation, Jimusar Sag, Junggar Basin, using organic petrology and rock pyrolysis as well as kerogen element and Fourier transform infrared (FT-IR) spectroscopy analyses, and compared the hydrocarbon generation mechanisms of source rocks with different types of organic matter. The organic matter of the Lucaogou Formation contains mostly two types of hydrocarbon generating macerals, the lamalginite and the telalginite based on physical and optical properties (texture, fluorescence, and optical reflectance). The lamalginite is a continuous sheet of less than 5 μm thick and greater than 50 μm in length. It has strong yellow fluorescence. The telalginite occurs as discontinuous short strips or pear-shaped objects with length of 10–30 μm and relatively weak fluorescence. The lamalginite-dominated shale has higher atomic H/C and lower atomic O/C ratios, indicating better hydrocarbon generation potential, whereas the telalginite-dominated shale has higher N and S heteroatom contents. The results of FT-IR spectroscopy of the kerogen indicate that the lamalginite-dominated shale is rich in aliphatic groups with long linear methylene sequences. The aromatic groups content is relatively low, but the carboxyl/carbon group (Cdouble bondO) content is high. The aliphatic group content of the telalginite-dominated shale is relatively low, with short-branched chains. The aromatic group content is relatively high. The methyl vibration signal directly connected to the benzene ring is strong, and the sulfoxide (Sdouble bondO) group has a high-intensity peak. Our results provide new insights into distinguishing organic matter types in the Lucaogou Formation and understanding the hydrocarbon generation mechanisms of source rocks in saline lake basins.

安徽官山两种坡缕石粘土的成分与红外吸收谱

本文采用多种成分分析手段对官山两种不同颜色坡缕石全粘土进行了研究。全粘土湿化学分析扣除SiO2 含量计算得到的坡缕石阳离子数与电子探针获得的阳离子数一致。配位八面体阳离子计算表明 ,粉红色坡缕石为三八面体矿物 ,灰白色坡缕石是介于三八面体矿物和二八面体矿物间的中间类型。X射线粉末衍射的K值法对全粘土矿物定量分析有着较高的精度 ,同时用电子探针波谱可准确测定坡缕石粘土的成分。官山两种不同颜色含坡缕石的全粘土红外吸收谱能反映其中坡缕石的吸收谱特征。对X射线光电子能谱研究表明两种不同颜色的坡缕石中的铁主要是Fe3+,这与全岩湿化学分析的结果是一致的 ,同时也还可以作为电子探针成分分析的补充。

Design of Uncooled Thermal Imaging Systems Operating at Multiple Temperatures

The reasons why thermal imaging systems consume power are analyzed,and a low power consumption design scheme is presented for the thermal imaging systems operating at multiple temperatures. The relation between the response performance of α-Si microbolometer detector and its operating temperature is studied by means of formulas of microbolometer detector's noise equivalent temperature difference(NETD) and detectivity. Numerical analysis based on true parameters demonstrates that the detectivity decreases slightly and NETD increases slightly when operating temperature rises,which indicates that α-Si microbolometer detector has approximately uniform response in a wide operating temperature range. According to these analyses,a thermal imaging system operating at multiple temperatures is designed. The power of thermoelectric stabilizer(TEC) is less than 350 mW and NETD is less than 120 mK in the ambient temperature range of-40 ℃-60 ℃,which shows that this system not only outputs high-quality images but consumes low power.

Possible Thermal Brightness Temperature Anomalies Associated with the Yutian (China) M_S7.3 Earthquake on February 12,2014

In order to analyze the seismic brightness temperature anomalies associated with the Yutian earthquake which occurred at Yutian County, Xinjiang on February 12,2014, daily brightness temperature data was collected from the China Geostationary Meteorological Satellite FY-2E,for the period from May 1,2012 to April 30,2014 and the geographical extent of 30°- 45°N latitude and 70°- 95°E longitude. The continuous wavelet transform method was used to analyze the relative wavelet power spectrum( RWPS) of brightness temperature data for each pixel. And the RWPS time-spatial evolution within the analysis area was obtained. The results showed that the anomaly started to appear at the vicinity of epicentre since October 2013, and anomalous areas gradually enlarged and stretched towards to Altun fault zone and the eastern part of West Kunlun fault zone. Anomalies began to appear at fault zones at Middle Tianshan Mountains, Southern Tianshan Mountains and the western part of the West Kunlun Mountains area which is located at the western margin of Tarim basin,since November 2013. Then anomalous area further enlarged and gathered along fault zones,and eventually,anomalous belts were developed along fault zones around the Tarim basin. The anomaly area and amplitude reached their maximum in late December 2013 and early January 2014. With the impending earthquake,the anomaly area and amplitude dwindled. Anomalies at the vicinity of epicentre disappeared days before the occurrence of the main shock. However, the anomaly at Altun and Middle Tianshan areas still remained. After the main shock,the anomaly attenuated quickly and the whole anomaly disappeared in late February 2014.