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A kind of novel broad-band superluminescent diodes (SLDs) using graded tensile-strained bulk InGaAs is developed. The graded tensile-strained bulk InGaAs is obtained by changing only group-Ⅲ trimethylgallium source flow during low-pressure metal organic vapor-phase epitaxy. At the injection current of 200mA, the fabricated SLDs with such structure demonstrate full-width at half-maximum spectral width of 106 nm and the output light power of 13.6 mW, respectively. 相似文献
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Growth of High-Quality GaAs on Ge by Controlling the Thickness and Growth Temperature of Buffer Layer 下载免费PDF全文
In the last two decades, m-v compound semi- conductor materials grown on elemental semiconduc- tor substrates have attracted much attention due to their potential applications in high-efficiency so- lar cells, photodetectors, quantum-dot (QD) lasers, and metal-oxide-semiconductor field-effect transistors (MOSFETs). Due to their extremely high electron mobility, III-V semiconductors such as GaAs, InGaAs and InAs are believed to be chan- nel materials for future complementary metal-oxide- semiconductor (CMOS) technology.CMOS tran- sistors on Ge substrates with high mobility In- GaAs/Ge channels have already been fabricated by using a wafer bonding technique, which is a promis- ing step for such a device on Si. 相似文献
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首次制备了Fe(Ⅲ)改性修饰的海藻酸钠微球作为固相微萃取材料,用该微球装载的微柱能够在不同形态砷化物共存时选择性富集水样中As(Ⅴ)。结合氢化物发生-原子荧光光谱法,可以实现实际水体样中无机As(Ⅲ)和As(Ⅴ)的形态分析。具体过程为:(1)以0.1mol·L-1柠檬酸为介质,在填充柱后流出液中选择性测定As(Ⅲ);(2)以20g·L-1硫脲-10g·L-1抗坏血酸溶液为预还原剂,5%盐酸为介质,测定不经过微萃取柱分离的原始水体样品中无机总砷(As(Ⅲ)和As(Ⅴ)),然后以差减法计算As(Ⅴ)的量。Fe(Ⅲ)改性海藻酸钠微球制备过程简便,成本低廉、绿色环保,相应基于Fe(Ⅲ)改性海藻酸钠微球微萃取过程的砷形态分离分析微萃取柱及其光谱联用技术,可以有效、快速地测定自然水体中As(Ⅲ)和As(Ⅴ),具有实际意义。 相似文献
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采用超低压(22 mbar)选择区域生长(Selective Area Growth, SAG)金属有机化学汽相沉积(Metal-organic Chemical Vapor Deposition, MOCVD)技术成功制备了高质量InGaAsP/InGaAsP多量子阱(Multiple Quantum Well, MQW)材料. 在较小的掩蔽宽度变化范围内(15—30μm),得到了46nm的光荧光(Photoluminescence, PL)波长偏移量,PL半高宽(Full-Width-at-Half-
关键词:
超低压
选择区域生长
渐变掩蔽图形 相似文献
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A novel distribute feedback (DFB) laser which gave two different wavelengths under two distinct work conditions was fabricated. The laser consists of two Bragg gratings with different periods corresponding to wavelength spacing of 20 nm in an identical active area. When driving current was injected into one of the different sections separately, two different wavelengths at 1542.4 and 1562.5 nm were realized. The side mode suppression ratio (SMSR) of 45 dB or more both for the two Bragg wavelengths were achieved. The fabricating process of the laser was just the samp as that of traditional DFB laser diode. This device can be potentially used in coarse wavelength division multiplexer (CWDM) as a promising light source and the technology idea can be used to enlarge the transmission capacity in metro area network (MAN). 相似文献
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提出了一种顺序流动注射-氢化物发生-原子吸收光谱分析方法。食品样品经硝酸-高氯酸(4+1)混合酸消化,以硼氢化钾为还原剂,盐酸溶液为载流,用氢化物发生-原子吸收光谱法测定食品中铅、镉和汞含量的方法。在优化的试验条件下,铅、镉和汞的质量浓度分别在一定的范围内与其吸光度呈线性关系,检出限(3s/k)分别为0.20,0.04... 相似文献
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氢化物发生-原子荧光光谱法测定海水中As(Ⅲ)和As(Ⅴ) 总被引:1,自引:0,他引:1
提出了一种断续流动注射氢化物发生-原子荧光光谱法测定海水中砷的方法.优化了流动注射氢化物反应发生条件为:5.0%盐酸-0.1 mol·L-1柠檬酸为载流和样品介质,2%KBH4-0.5%KOH还原剂,用氩气将产生的砷化氧带入氢氩焰中原子化,原子荧光光谱法检测.有机砷在此实验条件下不形成干扰,As(Ⅴ)须经预还原后测定.分析了青岛栈桥海滨浴场等海域采集的实际海水样品,实验结果表明海水样品中有机砷含量低,在大批量样品测定时,测定海水中As(Ⅲ)和As(Ⅴ)的量可以近似反映近海海域中砷污染情况. 相似文献
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树指标集马氏链的常返性 总被引:1,自引:0,他引:1
用鞅方法给出了在不限定根顶点O的条件下,树指标集马氏链常返性的充分条件,部分解决了Benjamin.I提出的问题. 相似文献