Carrier Lifetime Studies in Diode Structures on Si Substrates with and without Ge Doping

Results are presented of a comparative study of diodes processed on n-type Cz grown Si substrates without and with Ge doping concentration of about 1019 cm-3 and 1020 cm-3. In order to investigate thermal donor formation, isothermal annealing at 450°C for 0.5 – 5 h was carried out. As processed diodes were also irradiated with 2 MeV electrons with fluences in the range between 1014 and 1017 e/cm2 to investigate the Ge doping influence on irradiation induced defect formation. Diodes after thermal and radiation treatments have been investigated by combining different techniques.

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Ring‐Like Defect Formation in N‐Type Czochralski‐Grown Silicon Wafers during Thermal Donor Formation

physica status solidi (a) ◽

10.1002/pssa.202000587 ◽

2020 ◽

pp. 2000587

Author(s):

Rabin Basnet ◽

Hang Sio ◽

Manjula Siriwardhana ◽

Fiacre E. Rougieux ◽

Daniel Macdonald

Keyword(s):

Defect Formation ◽

Silicon Wafers ◽

Thermal Donor ◽

Donor Formation

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Correlations between thermal donor formation, rod-like defect formation, and oxygen reduction during low-temperature annealing of CZ-grown silicon

phys stat sol (a) ◽

10.1002/pssa.2211070240 ◽

1988 ◽

Vol 107 (2) ◽

pp. 851-865 ◽

Cited By ~ 24

Author(s):

M. Reiche ◽

J. Reichel ◽

W. Nitzsche

Keyword(s):

Low Temperature ◽

Oxygen Reduction ◽

Defect Formation ◽

Thermal Donor ◽

Low Temperature Annealing ◽

Donor Formation

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Enhanced Formation of Thermal Donors in Germanium Doped Czochralski Silicon Pretreated by Rapid Thermal Annealing

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.131-133.393 ◽

2007 ◽

Vol 131-133 ◽

pp. 393-398 ◽

Cited By ~ 2

Author(s):

Xin Zhu ◽

De Ren Yang ◽

Ming Li ◽

Can Cui ◽

Lei Wang ◽

...

Keyword(s):

Low Temperature ◽

Thermal Annealing ◽

Rapid Thermal Annealing ◽

Furnace Annealing ◽

Thermal Donor ◽

Low Temperature Annealing ◽

Initial Stage ◽

Donor Formation ◽

Oxygen Precipitates ◽

Ge Doping

The thermal donor formation at 425oC - 450oC in Ge doped Czochralski (GCZ) silicon having about 1016 cm-3 Ge content pretreated by rapid thermal annealing (RTA) and conventional furnace annealing (CFA) has been investigated using low-temperature infrared spectroscopy (LT-IR). The measurements prove that lightly Ge doping can enhance the formation of thermal double donors in the initial stage of the low temperature annealing after RTA process. Ge induced additional grown-in oxygen precipitates during silicon ingot growth and the abundant self-interstitials during RTA may be the reason for the enhancement. However, after extending the annealing time at the low temperatures, the thermal donor concentration in the GCZ silicon is lower than that in the conventional CZ silicon. In final, the mechanism is also discussed.

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"New Donors" in Czochralski Grown Silicon Annealed at T≥ 600°C under Compressive Stress

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.108-109.181 ◽

2005 ◽

Vol 108-109 ◽

pp. 181-186 ◽

Cited By ~ 1

Author(s):

Valentin V. Emtsev ◽

Boris A. Andreev ◽

Gagik A. Oganesyan ◽

D.I. Kryzhkov ◽

Andrzej Misiuk ◽

...

Keyword(s):

Mechanical Stress ◽

Compressive Stress ◽

Reference Temperature ◽

Enhancement Effect ◽

Shallow Acceptor ◽

Thermal Donor ◽

Compressive Stresses ◽

Heat Treated ◽

Donor Formation ◽

New Donors

Effects of compressive stress on oxygen agglomeration processes in Czochralski grown silicon heat treated at T= 450OC, used as a reference temperature, and T= 600OC to 800OC are investigated in some detail. Compressive stresses of about P= 1 GPa lead to enhanced formation of Thermal Double Donors in materials annealed over a temperature range of T= 450OC – 600OC. It has been shown that the formation of thermal donors at T= 450OC under normal conditions and compressive stress is accompanied with loss of substitutional boron. In contrast, the concentration of the shallow acceptor states of substitutional boron in silicon annealed under stress at T≥ 600OC remains constant. An enhancement effect of thermal donor formation is gradually weakened at T≥ 700OC. The oxygen diffusivity sensitive to mechanical stress is believed to be responsible for the observed effects in heat-treated silicon.

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Numerical Investigation of Graphene as a Back Surface Field Layer on the Performance of Cadmium Telluride Solar Cell

Molecules ◽

10.3390/molecules26113275 ◽

2021 ◽

Vol 26 (11) ◽

pp. 3275

Author(s):

Devendra KC ◽

Deb Kumar Shah ◽

M. Shaheer Akhtar ◽

Mira Park ◽

Chong Yeal Kim ◽

...

Keyword(s):

Solar Cells ◽

Solar Cell ◽

Doping Concentration ◽

Carrier Lifetime ◽

Short Circuit ◽

Back Surface ◽

Back Surface Field ◽

Cdte Solar Cell ◽

Cdte Solar Cells ◽

Surface Field

This paper numerically explores the possibility of ultrathin layering and high efficiency of graphene as a back surface field (BSF) based on a CdTe solar cell by Personal computer one-dimensional (PC1D) simulation. CdTe solar cells have been characterized and studied by varying the carrier lifetime, doping concentration, thickness, and bandgap of the graphene layer. With simulation results, the highest short-circuit current (Isc = 2.09 A), power conversion efficiency (h = 15%), and quantum efficiency (QE ~ 85%) were achieved at a carrier lifetime of 1 × 103 ms and a doping concentration of 1 × 1017 cm−3 of graphene as a BSF layer-based CdTe solar cell. The thickness of the graphene BSF layer (1 mm) was proven the ultrathin, optimal, and obtainable for the fabrication of high-performance CdTe solar cells, confirming the suitability of graphene material as a BSF. This simulation confirmed that a CdTe solar cell with the proposed graphene as the BSF layer might be highly efficient with optimized parameters for fabrication.

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