Multi-sheet InGaN quantum dots grown by a new method is reported

which is much different from the present quantum dots growth method. The dots are formed by de creasing the growth temperature and increasing the adatom-hopping-energy barrier through surface passivation. Thus the new method can be called as a passivation-low-temperature (PLT) method. Atomic force microscopy measurement reveal that the monolayer InGandots were small enough to expect zero-dimensional quantum effects. The size of monolayer QDs is typically 40nm wide and 15nm high. The QDs on upper layer can be grown bigger. The photoluminescence of (0001) InGaN multi-sheet QDs is measured. The PL spectra of (0001) InGaN/GaN multiple layers QDs show not only the QDs-related peak but also an additional peak. This phenomenon is attributed to the strong spontaneous and piezoelectric field along the (0001) orientation. Temperature dependent PL studies reveal the strongly zero-dimensional character of this QDs system. The experimental results show that

while for temperatur es lower than 50～60K and higher than 160K the peak energies follow the Varshni law

at the intermediate temperatures the energies decrease with increasing temperatures at a rate 6 times higher than that given by the Varshni law. The very similar phenomena were also observed in InAs QDs system. The temperature dependent PL and the AFM studies make sure that the QDs is successfully fabricated by PLT method.