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Abstract—Unlike the traditional tube-furnace annealing at 875 °C, rapid thermal annealing (RTA) and laser annealing offer flexibility, high throughput, and control of the heating and cooling rates and holding times for effective crystallization, dopant activation, and passivation quality in the B-doped p-TOPCon device. A comprehensive scientific understanding of the effects of RTA is required. Slower RTA heating (≤ 798 K/min) and cooling (≤ 156 K/min) rates and optimal 60 s holding time at 825 °C enhanced the passivation quality, which was further improved by post anneal forming gas annealing (FGA). Faster heating and cooling rates (≥ 4800 K/min) damaged the passivation quality irreversibly and did not improve further by FGA. The optimized RTA parameters yielded iVoc of 638 mV and sheet resistance of ∼1.0 kΩ/sq. The dopant activation was independent of the heating and cooling rates.
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Study of flashlamp annealing to promote crystallization of indium tin oxide thin films
The use of flashlamp annealing as a low-temperature alternative or supplement to thermal annealing is investigated. Flashlamp annealing and thermal annealing were conducted on 100 nm thick indium tin oxide (ITO) films deposited on glass to compare the properties of films under different annealing methods. The ITO samples had an average initial sheet resistance of 50 Ω/sq. After flashlamp annealing, the sheet resistance was reduced to 33 Ω/sq only, while by thermal annealing at 210 °C for 30 min, a sheet resistance of 29 Ω/sq was achieved. Using a combination of flashlamp annealing and thermal annealing at 155 °C for 5 min, a sheet resistance of 29 Ω/sq was achieved. X-ray diffraction analysis confirmed that flashlamp annealing can be used to crystallize ITO. Flashlamp annealing allows for low-temperature crystallization of ITO on a time scale of 1–3 min. Through electrical and optical characterizations, it was determined that flashlamp annealing can achieve similar electrical and optical properties as thermal annealing. Flashlamp offers the method of low-temperature annealing, which is particularly suitable for temperature sensitive substrates.
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- Award ID(s):
- 2243110
- PAR ID:
- 10510863
- Publisher / Repository:
- AIP Publishing
- Date Published:
- Journal Name:
- Journal of Applied Physics
- Volume:
- 134
- Issue:
- 23
- ISSN:
- 0021-8979
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1063/5.0177627
