Makita, K.K.MakitaKamikawa, Y.Y.KamikawaMizuno, H.H.MizunoOshima, R.R.OshimaShoji, Y.Y.ShojiIshizuka, S.S.IshizukaMüller, RalphRalphMüllerBeutel, PaulPaulBeutelLackner, DavidDavidLacknerBenick, JanJanBenickHermle, MartinMartinHermleDimroth, FrankFrankDimrothSugaya, T.T.Sugaya2022-03-062022-03-062021https://publica.fraunhofer.de/handle/publica/26766710.1002/PIP.3398Multijunction (MJ) solar cells achieve high efficiencies by effectively utilizing the solar spectrum. Previously, we have developed III-V MJ solar cells using smart stack technology, a mechanical stacking technology that uses a Pd nanoparticle array. In this study, we fabricated an InGaP/AlGaAs//CuxIn1−yGaySe2 three-junction solar cell by applying modified smart stack technology with a Pd nanoparticle array and adhesive material. Using adhesive material (silicone adhesive), the bonding stability was improved conspicuously. The total efficiency achieved was 27.2% under AM 1.5 G solar spectrum illumination, which is a better performance compared to our previous result (24.2%) for a two-terminal solar cell. The performance was achieved by optimizing the structure of the upper GaAs-based cell and by using a CuxIn1−yGaySe2 solar cell with a specialized performance for an MJ configuration. In addition, we assessed the reliability of the InGaP/AlGaAs//CuxIn1−yGaySe2 three-junction solar cell through a heat cycle test (from −40°C to +85°C; 50 cycles) and were able to confirm that our solar cells show high resistivity under severe conditions. The results demonstrate the potential of III-V//CuxIn1−yGaySe2 MJ solar cells as next-generation photovoltaic cells for applications such as vehicle-integrated photovoltaics; they also demonstrate the effectiveness of modified smart stack technology in fabricating MJ cells.enPhotovoltaikbonding technologyCuxIn1-yGaySe2 solar cellsIII-V solar cellsmechanical stackmultijunction solar cellsIII-V- und Konzentrator-PhotovoltaikIII-V Epitaxie und Solarzellen621697journal article