MOCVD Growth of MgZnO Nanotips Used for Hybrid Polymer Solar Cells

摘要: ZnO can be alloyed with MgO to form MgxZn1xO, tuning the direct band gap energy from 3.3 4.0 eV [1, 2]. Growth of 1-D wurtzite MgxZn1-xO nanotips is challenging than that films because solid solubility limit in only ~4% and growth nearly under thermal equilibrium. Recent study [3] shows Mg incorporation into MgxZn1-xO, tunes offset poly (3-hexylthiophene) (P3HT)-MgZnO hybrid solar cells, resulting an enhanced open circuit voltage VOC. In this work, are grown on various substrates, including Si, glass, Ga-doped (GZO) coated glass. For MOCVD diethylzinc (DEZn) bismethylcyclopentadienyl magnesium (MCp2Mg) used as Zn precursors, respectively. The parameters, Zn/O precursors flow rate ratio, temperature, chamber pressure optimized. structural optical properties characterized by X-ray diffraction (XRD), transmission, photoluminescence. Field emission scanning electron microscope (FESEM) check surface morphology nanotips. Finally, a novel 3-D photoelectrode structure, which consists film array single crystalline (0≤x≤0.10) make P3HT-MgxZn1-xO cells. It found optimum temperature for around 520C. At low (≤ 500C) or at high (≥ 550C), significant degradation transmission spectra observed. another sensitive factor, impacts incorporation. A (~60 torr) leads maximum 10% incorporating Figure 1 different composition, x (0≤x≤0.1) optimized ~ 60 torr. thin buffer plays critical role seed layer along [0001] direction Si glass substrates. (~10nm) initially ~520C before MgxZn1xO growth. inset figure FESEM image Mg0.07Zn0.93O substrates buffer. XRD measurements (Fig.2) confirm have crystal orientation direction. cells built GZO/glass GZO deposited ~380C. film, acting electrode window, has up 90% visible light region sheet resistance 40Ω/square. show similar P3HT onto spin coating. bandgap values UV-Vis absorption made ZnO, Mg0.04Zn0.96O Mg0.05Zn0.95O 3.42, 3.52 3.60 eV, open-circuit VOC increases ~100 mV ~180 Mg0.05Zn0.95O. simulated measured function contents good agreement. summary, we using MOCVD. polymer combined higher when increasing composition