In addition to the different technologies of silicon solar cells in crystalline form, TOPCon solar cells have an exceptionally great efficiency of 26%, accomplished by the manufacturing scale technique for industrialization, and have inordinate cell values of 732.3 mV open-circuit voltage (V_oc) and a fill factor (FF) of 84.3%. The thickness of tunnel oxide, which is less than 2 nm in the TOPCon cell, primarily affects the electrical properties and efficiency of the cell. In this review, various techniques of deposition were utilized for the layer of SiO_x tunnel oxide, such as thermal oxidation, ozone oxidation, chemical oxidation, and plasma-enhanced chemical vapor deposition (PECVD). To monitor the morphology of the surface, configuration of annealing, and rate of acceleration, a tunnel junction structure of oxide through a passivation quality of better V_oc on a wafer of n-type cell might be accomplished. The passivation condition of experiments exposed to rapid thermal processing (RTP) annealing at temperatures more than 900 °C dropped precipitously. A silicon solar cell with TOPCon technology has a front emitter with boron diffusion, a tunnel-SiO_x/n⁺-poly-Si/ SiN_x:H configuration on the back surface, and electrodes on both sides with screen printing technology. The saturation current density (J₀) for such a configuration on a refined face remains at 1.4 fA/cm² and is 3.8 fA/cm² when textured surfaces of the cell are considered, instead of printing with silver contacts. Following the printing of contacts with Ag, the J₀ of the current configuration improves to 50.8 fA/cm² on textured surface of silicon, which is moderately lesser for the metal contact. Tunnel oxide layers were deposited using many methods such as chemical, ozone, thermal, and PECVD oxidation are often utilized to deposit the thin SiO_x layer in TOPCon solar cells. The benefits and downsides of each approach for developing a SiO_x thin layer depend on the experiment. Thin SiO_x layers may be produced using HNO₃:H₂SO₄ at 60 °C. Environmentally safe ozone oxidation may create thermally stable SiO_x layers. Thermal oxidation may build a tunnel oxide layer with low surface recombination velocity (10 cm/s). PECVD oxidation can develop SiO_x on several substrates at once, making it cost-effective.

Crystalline silicon solar cells are highly efficient, but their long-term stability is compromised by Light and Elevated Temperature Induced Degradation (LeTID), which occurs under moderate illumination and elevated temperatures. While much research has focused on LeTID in multi-crystalline and monocrystalline silicon cells, with mitigation techniques like thermal treatments and optimized passivation, the use of alternating current (AC) biasing waveforms for LeTID mitigation and performance recovery has not been thoroughly explored. This study investigates the regeneration of a heterojunction with intrinsic thin-layer (HIT) solar cells (4 × 4 cm2), subjected to LeTID conditions (1 sun illumination at 75 °C for 11 h), using sinusoidal, square, and triangular AC waveforms at frequencies of 100 kHz, 500 kHz, and 1 MHz. LeTID exposure significantly reduced efficiency, open-circuit voltage (Voc), short-circuit current (Jsc), and fill factor (FF). After applying AC waveforms, substantial recovery was observed across all performance metrics, with square waveforms at 1 MHz providing the most significant recovery, restoring Voc, Jsc, FF, and efficiency to 99.99% of their initial values. Sinusoidal waveforms showed effective recovery, reaching 99%–99.5%, while triangular waveforms exhibited somewhat lower recovery, in the range of 97%–99%. These findings highlight the importance of waveform shape and frequency in facilitating hydrogen redistribution and defect passivation. The results suggest that high-frequency AC biasing techniques could be integrated into industrial processes to enhance the long-term stability and reliability of HIT solar cells, supporting the broader deployment of high-efficiency photovoltaic systems.

Light- and elevated-temperature-induced degradation (LeTID) affects materials used in solar cell fabrication, especially gallium- and boron-doped p-type, and various n-type silicon wafers. Dark annealing at elevated temperatures promotes hydrogen diffusion into the bulk of silicon wafers. Here, dark-annealing was consistently performed at 200 °C for 15 min to observe its impact on degradation and recovery. Higher temperatures accelerated LeTID, necessitating rapid annealing for regeneration. The chosen temperature range (75, 120, and 135 °C) was selected to simulate real-world solar panel operating conditions and to observe degradation under both moderate and extreme temperatures. Forming-gas annealing increased the carrier lifetime of boron-doped silicon wafers by up to 92.8% and gallium-doped wafers by up to 16.3% from their initial values after degradation. Dark-annealing resulted in 40% and 28% increases in the carrier lifetimes of fully degraded gallium- and boron-doped silicon wafers, respectively. The proposed model explains the behavior related to different diffusivities of hydrogen in gallium- and boron-doped silicon wafers during dark-annealing. The LeTID mechanism involves three stages: generating inactive recombination centers (Dⁱ) and H⁺ ions during manufacturing, converting Dⁱ to HDⁱ⁺¹, enhancing carrier recombination, and, during regeneration, the injection of carriers (e⁻) transitions to a recombination inactive state.

Floating photovoltaic (FPV) systems are emerging as a solution for land-constrained renewable deployment, yet their energy yield is often limited by the low albedo of water surfaces. Although bifacial modules and advanced cell technologies can mitigate this problem, little work has systematically compared their performance under FPV conditions. This study employs PVsyst 7.2 to simulate a 2 MW bifacial FPV plant on Boryeong Lake, South Korea, assessing the combined effects of orientation, tracking, and three leading technologies, PERC, TOPCon, and HJT. Results show that bifacial modules produce about 5% more energy than monofacial ones, and single-axis tracking raises output by 20% relative to fixed-tilt systems. Among the cell types, HJT achieved the highest annual yield, outperforming PERC and TOPCon due to its lower temperature coefficient and higher bifaciality. These findings highlight the importance of technology selection and system design in maximizing FPV performance and provide quantitative guidance for future FPV deployment. The study also establishes a simulation baseline for validating experimental FPV projects in diverse climates.