Search

31st European Photovoltaic Solar Energy Conference and Exhibition; 645-647, Silicon heterojunction (SHJ) solar cell have potential to achieve high efficiencies and rear emitter SHJ solar cell structure was more widely studied. We reported that the effect of n-type hydrogenated amorphous silicon (n a-Si:H) and intrinsic hydrogenated amorphous silicon (i a-Si:H) layer thickness on SHJ solar cell. Minority carrier life time (MCLT) and implied Voc increase with increasing n a-Si:H layer thickness or i a-Si:H layer thickness. Based on MCLT data, surface passivation quality is stronger correlated to i a-Si:H layer thickness rather than n a-Si:H layer thickness. The result show that open-circuit voltage (Voc) increases, whereas fill factor (FF) and short-circuit current density (Jsc) reduces with increasing i a-Si:H layer thickness. The highest cell efficiency can be achieved by optimizing i a-Si:H layer thickness. While n a-Si:H layer thickness is too thin, Voc, Jsc and FF will obviously drop. Comparing with rear emitter SHJ solar cell to front emitter SHJ solar cell, rear emitter SHJ solar cell shows higher efficiency due to higher Jsc and fill factor FF.

31st European Photovoltaic Solar Energy Conference and Exhibition; 884-886, Silicon heterojunction (SHJ) solar cells have potential to achieve high efficiencies. Among many process parameters, wafer quality plays an important role in determining the efficiency of a solar cell. The correlation between wafer quality and cell performance was investigated. The wafers in the top, middle, and bottom parts of each ingot were taken and tested. The results from JV-curve measurements revealed that the decreased efficiencies may be due to ambiguous and dark edges of cells shown in photoluminescence imaging, indicating low quality of wafers. After optimizing cell process with a fine quality of wafer, SHJ solar cell on a 6 inch n-mono wafer with a conversion efficiency of 23.43 % was achieved by AUO HJ-RD team.

31st European Photovoltaic Solar Energy Conference and Exhibition; 729-731, The influence of front-side transparent conduction oxide films in the performance of silicon heterojunction solar cells with the front-emitter and the rear-emitter structures was investigated. The characteristic of the transparent conduction oxide films was examined. The increase in oxygen contents of transparent conduction oxide films significantly increased the short current density, and decrease the fill factor of fabricated cells using the corresponding films. In comparison with the front emitter, the fill factor decreased slightly for the rear emitter. Due to n-type conductivity of transparent conduction oxide in the rear-emitter solar cells, the toleration of the electrical property of transparent conduction oxide was thought to be extensive, which promoted the majority carriers (electrons) to collect and transport to the electrodes. Using rear emitter is believed to be able to effectively increase the short current density and keep the fill factor, thereby increasing cell efficiency. The efficiency of the rear-emitter HJT solar cell was 23.4% .

31st European Photovoltaic Solar Energy Conference and Exhibition; 890-892, The silicon heterojunction (SHJ) technology is evolving rapidly with new concepts and ideas for systematically improve efficiency and decrease cost. Using the sputtered NiV/Ag film to substitute standard screen printing technology in the back side is common method to reduce the cost. In this work, we report on the first observation of the adhesives problem in the interface between Ag film and transparent conducting oxide (TCO) layer when the ribbons are standard soldering on the cell, and propose ways to improve it. This work focuses on analyzing the interface and adhesion for heterojunction solar cells. Especially the formed amorphous on TCO layer will be discussed and compared to standard without amorphous TCO layer. Electrical characterizations, adhesive strength tests have been used to quantify the characteristics of the cell performance. It will be shown that a long term stable structure with amorphous TCO layer is possible with industrial methods.

Physical size and strength are associated with dominance and threat. The current study tested (i) whether men’s evaluations of male strangers would be negatively influenced by cues indicating physical formidability, and (ii) whether these evaluations would be influenced by oxytocin, a neuropeptide that mediates social behavior and reduces social anxiety. In a placebo-controlled double-blind design, we administered either oxytocin (24 I.U.) or placebo intranasally to 100 healthy males and assessed their responses to an image of either a physically formidable (strong) or physically non-formidable (weak) male peer. Whereas participants receiving placebo expressed dislike and avoidance of the strong male relative to the weak male, oxytocin selectively improved social evaluation of the strong male. These results provide first evidence that oxytocin regulates social evaluation of peers based on body features indicating strength and formidability. We discuss the possibility that oxytocin may promote the expansion of social networks by increasing openness toward potentially threatening individuals.

29th European Photovoltaic Solar Energy Conference and Exhibition; 1352-1354, A conversion efficiency of 22.75 % for silicon heterojunction (SHJ) solar cells using standard 40 um finger width of copper electroplating process has been successfully achieved in our RD line at AU Optronics (AUO). However, 40 um finger width of copper (Cu) electroplating (EP) technique has encountered difficulties for further efficiency improvements. Our power loss simulation reveals efficiency gains from fine fingers. AUO solar RD team has been developing a new manufacturing technology by employing 20 um finger width of Cu EP to improve shortcircuit current. Both the experimental result and theoretical calculation show that the total power loss of 20 um finger width and optimum TCO film resistance of Cu EP cells is much smaller than the power loss from the state of 40 um finger width technique. According to the simulation result, an efficiency of more than 23.1% is achievable by our unique metallization technique.

29th European Photovoltaic Solar Energy Conference and Exhibition; 1081-1083, 23.11% of silicon heterojunction solar cells (HJT) on 6 inch wafers were fabricated using new structure of transparent conduction oxide (TCO) layers. The influences of synthesis conditions in the optical properties of TCO were investigated. The use of new structure of TCO layers were observed to exhibit high short current density and high fill factor. The results of J-V curve indicated that an increase in the thickness of rear-side TCO layers significantly increased the short current density of HJT cells. No light induced degradation (LID) after 48hrs was demonstrated for HJT cells. In addition, the 60-cell module was fabricated using 3 Busbar soldering process. The performance of 323.5Wwas achieved.

29th European Photovoltaic Solar Energy Conference and Exhibition; 484-486, Silicon heterojunction (SHJ) solar cell have potential to achieve high efficiencies. We reported that minority carrier life time (MCLT) result indicate a wide range of 600 μs to 2600 μs and implied Voc data indicate a wide range of 704 mV to 728 mV after a-Si deposited on texture wafer in trail production. This variation of MCLT may be attributed to CZ wafer quality, texture process, or PECVD. The statistical data of efficiency is widely distributed due to different batch process and configuration at the p-n heterojunction. The average efficiency of 21.23 % and Voc of 718 mV were achieved in the best batch of trail production. The highest efficiency SHJ solar cell of 21.6 % was achieved in trail production. The output power of 301.4 W and the module efficiency of 18.7 % were achieved. After optimization of cell process, SHJ solar cell on 6 inch wafers with an average conversion efficiency of 22 % and Voc of 720 mV were achieved by AUO HJ-RD team.