31. A band gap is the range in a solid where no electron state can exist. 32. In a regular semiconductor crystal, the band gap is fixed owing to continuous energy states. 33. Most ( though not all, see Mott insulator ) insulators have a large band gap . 34. When Wigner crystallization occurs, jellium acquires a band gap . 35. The addition of silicon to hafnium oxide increases the band gap , while decreasing the dielectric constant. 36. However, it performs poorly ( providing limited brightness ) because it has an indirect band gap . 37. Using this method, the local electronic structure of semiconductors in the band gap can be probed. 38. In indirect band gap semiconductors, the carrier lifetime strongly depends on the concentration of recombination centers. 39. It can be shown that the energies of these states all lie within the band gap . 40. The light must pass through the band gap .
