A heterojunction is a boundary formed between two different semiconductor materials, each with distinct electronic properties. This junction allows for the efficient movement of charge carriers, such as electrons and holes, which is essential in various electronic devices. Heterojunctions are commonly used in devices like solar cells and light-emitting diodes (LEDs) to enhance performance. The unique characteristics of a heterojunction arise from the differing energy band structures of the two materials. For example, combining materials like gallium arsenide and indium phosphide can create a more efficient pathway for electrical conduction. This technology plays a crucial role in modern electronics and optoelectronics.