Question

dentify a semiconducting material and provide the value of its band gap) that could be used in: (a) (1 point) red LED (b) (1 point) UV LED c) (1 point) infrared detector (d) (1 point) blue LED (e) (1 point) green LED

Answer 1

Answer:

(a) Aluminum Indium Gallium Phosphide (AlInGaP). Band gap = 1.81eV  ≈ 2eV

(b) Gallium Nitride (GaN). Band Gap = 3.4eV

(c) Aluminium Gallium Arsenide (AlGaA). Band Gap = 1.42eV ≈ 2.16eV

(d) Zinc Selenide (ZnSe). Band Gap = 2.82eV

(e) Gallium Phosphide (GaP). Band Gap = 2.24eV

Explanation:

LED's are semi-conducting materials that convert electrical energy to light energy. The light color emitted from the LED depends on the semi-conducting material and other compositions.

The band gap of the semi-conductor determines its wavelength. High band gap semi-conductors emit lower wavelengths which means greater power(UV semi-conducting macterials fall under this category).