GRADED BAND GAP MULTIPLE QUANTUM WELL SOLAR CELL

• Main Authors: KHURGIN, JACOB, SAIF, BABAK
• Format: Patent
• Language: English; French
• Published: 28.06.2001
• Edition: 7
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; NANOTECHNOLOGY; PERFORMING OPERATIONS; REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGYGENERATION, TRANSMISSION OR DISTRIBUTION; SEMICONDUCTOR DEVICES; SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS; TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINSTCLIMATE CHANGE; TRANSPORTING

A solar cell is configured to include a nanostructure called a superlattice. The band gaps of the superlattice are graded so as to provide for broader absorption of incident light energy for conversion into charge carrier pairs. Preferably, the superlattice is formed so that the thickness of the barriers and wells vary along the crystal growth axis of the device. The dimensions of the barriers increase stepwise along the growth axis, whereas the dimensions of the wells decrease stepwise along the growth axis. By varying the relative widths of the barriers and wells, the widths of the minibands in the superlattice are graded. L'invention concerne une cellule solaire configurée de façon à renfermer une nanostructure appelée hétérostructure. La progression des largeurs de bande interdite de l'hétérostructure est telle qu'elle permet d'absorber plus largement l'énergie lumineuse incidente afin de la convertir en paires de porteurs de charge. L'hétérostructure est, de préférence, formée de sorte que l'épaisseur des barrières et des puits varie le long de l'axe de croissance du cristal de l'appareil. Les dimensions des barrières augmentent progressivement le long de l'axe de croissance tandis que les dimension des puits se réduisent progressivement le long dudit axe de croissance. Du fait de la variation des largeurs relatives de barrières et des puits, les largeurs des minibandes de l'hétérostruture progressent.