Ask Question
5 November, 23:39

Solar cells are given antireflection coatings to maximize their efficiency. Consider a silicon solar cell (n = 3.50) coated with a layer of silicon dioxide (n = 1.45). What is the minimum coating thickness that will minimize the reflection at the wavelength of 700 nm, where solar cells are most efficient?

+3
Answers (1)
  1. 6 November, 03:11
    0
    t = 121 nm

    Explanation:

    Given:

    - Silicon refractive index n_1 = 3.50

    - Silicon dioxide refractive index n_2 = 1.45

    - The wavelength of light in air λ_air = 700 nm

    Find:

    What is the minimum coating thickness that will minimize the reflection at the wavelength of 700 nm.

    Solution:

    - The film's index of refraction (n_2 = 1.45) is less than that of solar cell (n_1 = 3.50) so there will be a reflective phase change at the first boundary (air-film), and at the second boundary (film-solar cell). The relationship for destructive interference for two reflective phase changes is as follows:

    2*t = (m + 0.5) * (λ/n_2) m = 0, 1, 2, ...

    - Solve for thickness t where m = 0 (for the thinnest film).

    t = 0.25 * (λ/n_2)

    t = 0.25 * (700/1.45)

    t = 121 nm ... (rounded to 3 sig. fig)

    - This coating technique is important to increase the efficiency of solar cells; If the light can't reflect, then it must transmit into the solar cell material.
Know the Answer?
Not Sure About the Answer?
Find an answer to your question ✅ “Solar cells are given antireflection coatings to maximize their efficiency. Consider a silicon solar cell (n = 3.50) coated with a layer of ...” in 📘 Physics if you're in doubt about the correctness of the answers or there's no answer, then try to use the smart search and find answers to the similar questions.
Search for Other Answers