Fig nbsp xA SEM image

Under high PH3PH3 flux (2.7 sccm), both increase and decrease of the growth temperatures than 490 °C show the rise of FWHM of AlGaP and roughness of cap layer. The growth temperatures below 490 °C might bring the insufficient mobility of group-III adatoms due to the low surface energy which may be the reason of the formation of defects while above 490 °C less availability of P2P2 may cause the defects.