The Extraction of Minority Carrier Lifetime from the Current-Voltage Characteristics of Si/Si1−xGex Devices

1991 ◽  
Vol 220 ◽  
Author(s):  
T. Ghani ◽  
J. L. Hoyt ◽  
D. B. Noble ◽  
J. F. Gibbons ◽  
J. E. Turner ◽  
...  

ABSTRACTThe extraction of recombination lifetime from the current-vol tage characteristics of diode structures containing Si1−xGex strained layers is discussed. Electrical measurements are used in conjunction with computer simulations to extract minority carrier lifetime in Si1−xGex layers with various oxygen concentrations. The minority carrier lifetime in Si1−xGex increases from several psec at an oxygen concentration of 2×1020 cm−3, to greater than 0.5 μs at concentrations below 3×1017 cm−3. The structures are analyzed for sensitivity of the current characteristics to Si1−xGex minority carrier lifetime. Calculations predict that the maximum lifetime which can be extracted from such structures is greater than 100 μsec. However, due to limitations imposed by perimeter currents, the maximum lifetime which can be extracted from our diode structures is on the order of 3 μsec. Maximizing area to perimeter ratio of the diode structures and moving the Si1−xGex-SiO2 interface away from the active device region is required in order to increase the maximum extracted lifetime from such structures.

1991 ◽  
Vol 225 ◽  
Author(s):  
Akira Usami ◽  
Yoshimaro Fujii ◽  
Hideki Fujiwara ◽  
Tomiyasu Sone ◽  
Takao Wada

ABSTRACTRecombination lifetime of a epitaxial layer (epilayer) is automatically measured by using the conductivity modulation technique. A lateral p+-n−-n+ diode test structure on the surface of the epilayer is formed to evaluate the minority carrier lifetime. Depth profiles of the recombination lifetime are obtained from current-voltage curves of a lateral p+-n−-n+ diode and a vertical n+-n−-n+ structure between the substrate and the top surface. We measure the lifetime in epilayers with and without a buffer-layer. In addition, photo-response of photodiodes with and without the buffer-layer is measured. Profiles of the recombination lifetime depend on the thickness of the epilayer but not on the thickness of the buffer-layer. Minority carrier lifetime in the epilayer, and the leakage current and the photo-response of photodiodes are improved by the buffer-layer formation between epilayer and substrate.


2013 ◽  
Vol 440 ◽  
pp. 82-87 ◽  
Author(s):  
Mohammad Jahangir Alam ◽  
Mohammad Ziaur Rahman

A comparative study has been made to analyze the impact of interstitial iron in minority carrier lifetime of multicrystalline silicon (mc-Si). It is shown that iron plays a negative role and is considered very detrimental for minority carrier recombination lifetime. The analytical results of this study are aligned with the spatially resolved imaging analysis of iron rich mc-Si.


2015 ◽  
Vol 242 ◽  
pp. 126-132 ◽  
Author(s):  
George Martins ◽  
Ruy S. Bonilla ◽  
Toby Burton ◽  
P. MacDonald ◽  
Peter R. Wilshaw

In this work we use Saw Damage Gettering (SDG) in combination with emitter formation to improve the minority carrier lifetime of highly contaminated multi-crystalline silicon wafers. This process is applied to wafers from the bottom of ingots, commonly referred to as the “red zone”, which are currently discarded since their high concentration of impurities limits the efficiency of solar cells produced therefrom. SDG is a potentially simple technique designed to upgrade these wafers. In this technique, bulk impurities are dissolved via annealing. The wafers are then cooled which generates a super-saturation of impurities in solution. The system then relaxes through the formation of precipitates in the saw damaged region. SDG is shown to be enhanced when using a temperature dependent cooling rate which maximizes the flux of impurities to the saw damaged regions. In addition, these benefits were observed even after an additional gettering process occurring during an emitter formation procedure. The SDG annealing conditions required to achieve the maximum lifetime were altered by the introduction of the emitter formation process. The enhancement generated by the SDG process may be sufficient to enable red-zone wafers to be processed is the same manner as higher quality no-red zone wafer wafers without adversely affecting the resultant cell efficiency. Due to its simplicity, it is expected that SDG can easily be incorporated into current production methods.


2013 ◽  
Vol 740-742 ◽  
pp. 633-636 ◽  
Author(s):  
Birgit Kallinger ◽  
Patrick Berwian ◽  
Jochen Friedrich ◽  
Mathias Rommel ◽  
Maral Azizi ◽  
...  

4H-SiC homoepitaxial layers with different thicknesses from 12.5 µm up to 50 µm were investigated by microwave-detected photoconductivity decay (µ-PCD), deep level transient spectroscopy (DLTS) and defect selective etching (DSE) to shed light on the influence of the epilayer thickness and structural defects on the effective minority carrier lifetime. It is shown that the effective lifetime, resulting directly from the µ-PCD measurement, is significantly influenced by the surface recombination lifetime. Therefore, an adequate correction of the measured data is necessary to determine the bulk lifetime. The bulk lifetime of these epilayers is in the order of several microseconds. Furthermore, areas with high dislocation density are correlated to areas with locally reduced effective lifetime.


2005 ◽  
Vol 483-485 ◽  
pp. 973-976 ◽  
Author(s):  
Pavel A. Ivanov ◽  
Michael E. Levinshtein ◽  
Tigran T. Mnatsakanov ◽  
John W. Palmour ◽  
Ranbir Singh ◽  
...  

Forward current-voltage characteristics, reverse current recovery and post-injection voltage decay are measured for high voltage 4H-SiC p+non+-diodes. The effects of both minority carrier lifetime in diode no-base and injection coefficient of p+-emitter are investigated with respect to device performance at high injection levels.


1971 ◽  
Vol 7 (25) ◽  
pp. 754
Author(s):  
R.E. Thomas ◽  
V. Makios ◽  
S. Ogletree ◽  
R. Mckillican

2019 ◽  
Vol 3 (6) ◽  
Author(s):  
Zhihao Xu ◽  
Denis A. Shohonov ◽  
Andrew B. Filonov ◽  
Kazuhiro Gotoh ◽  
Tianguo Deng ◽  
...  

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