| Summary: | 碩士 === 國立中興大學 === 精密工程學系所 === 104 === This study focused on using chemical selective etching (CSE) to fabricate GaAs thin-film solar cells and discussed their characteristics. Additionally, the technique of the recyclable GaAs substrate was developed and realized. This was not only able to obtain a high efficiency solar cell, but also reduce the fabrication cost. All GaAs solar cells were applied to mobile power packs for comparing their device performance.
Under CSE process, the AlAs was regarded as a sacrificial layer, which was be etched to assist in the separation of the solar cell epilayer from GaAs substrate. Then the GaAs substrate could be recycled for the next usage as a growth template. The finishing time of completely separating the whole epilayer from four-inch GaAs cell was about 6-10 hours. Thin film solar cells can be transferred to Ni substrate with high thermal dissipation and light weight by means of CSE process.
On the other hand, the recycled GaAs substrate was cleaned by the mixture solution of hydrogen peroxide and ammonia and the mixture solution of phosphoric acid and hydrochloric acid, and then it could be reused for the solar cell epitaxial growth by metal-organic chemical vapor deposition. Afterwards, this thin film solar cell was coated with the n-type electrode and an anti-reflective layer to increase the optical path for enhancing the photocurrent.
This thesis composed three parts. First of all, the influences of different skills including bending and unbending temporary substrates on the characteristics of solar cells were discussed. In the second part, four different areas of solar cells were designed, such as 0.03 cm2, 0.25 cm2, 0.64 cm2, and 1 cm2, respectively. In addition, the effects of distinct materials of anti-reflective layers and two kinds of base layer thicknesses on the characteristics of devices were also explored. Finally, the GaAs-based solar cells were actually used to fabricate a module of portable power source. Furthermore, the performance of the portable power source constructed by GaAs-based solar cell was compared with that built by commercial Si-based solar cells.
|
|---|
