GaAs p-i-n Photodiode Array on GaP Using Wafer Fusion

2015 ◽  
Vol 27 (5) ◽  
pp. 466-469
Author(s):  
Vaibhav Mathur ◽  
Shivashankar Vangala
Author(s):  
J. B. Warren

Electron diffraction intensity profiles have been used extensively in studies of polycrystalline and amorphous thin films. In previous work, diffraction intensity profiles were quantitized either by mechanically scanning the photographic emulsion with a densitometer or by using deflection coils to scan the diffraction pattern over a stationary detector. Such methods tend to be slow, and the intensities must still be converted from analog to digital form for quantitative analysis. The Instrumentation Division at Brookhaven has designed and constructed a electron diffractometer, based on a silicon photodiode array, that overcomes these disadvantages. The instrument is compact (Fig. 1), can be used with any unmodified electron microscope, and acquires the data in a form immediately accessible by microcomputer.Major components include a RETICON 1024 element photodiode array for the de tector, an Analog Devices MAS-1202 analog digital converter and a Digital Equipment LSI 11/2 microcomputer. The photodiode array cannot detect high energy electrons without damage so an f/1.4 lens is used to focus the phosphor screen image of the diffraction pattern on to the photodiode array.


Author(s):  
J. Barbillat ◽  
M. Delhaye ◽  
P. Dhamelincourt

Raman mapping, with a spatial resolution close to the diffraction limit, can help to reveal the distribution of chemical species at the surface of an heterogeneous sample.As early as 1975,three methods of sample laser illumination and detector configuration have been proposed to perform Raman mapping at the microscopic level (Fig. 1),:- Point illumination:The basic design of the instrument is a classical Raman microprobe equipped with a PM tube or either a linear photodiode array or a two-dimensional CCD detector. A laser beam is focused on a very small area ,close to the diffraction limit.In order to explore the whole surface of the sample,the specimen is moved sequentially beneath the microscope by means of a motorized XY stage. For each point analyzed, a complete spectrum is obtained from which spectral information of interest is extracted for Raman image reconstruction.- Line illuminationA narrow laser line is focused onto the sample either by a cylindrical lens or by a scanning device and is optically conjugated with the entrance slit of the stigmatic spectrograph.


2009 ◽  
Vol 38 (3) ◽  
pp. 359-363
Author(s):  
Jee-Eun Hong ◽  
Mi-Ran Kim ◽  
Sang-Hee Cheon ◽  
Jung-Young Chai ◽  
Eun-Ryong Park ◽  
...  

1985 ◽  
Vol 21 (17) ◽  
pp. 718 ◽  
Author(s):  
H. Nobuhara ◽  
O. Wada ◽  
T. Fujii
Keyword(s):  

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Fan Xu ◽  
Yuan-Qing Wang ◽  
Xiao-Fei Zhang ◽  
Cai-Yun Wang

A Correction to this paper has been published: https://doi.org/10.1038/s42005-021-00520-8.


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