Surface morphology and optical properties of InGaN quantum dots with varying growth interruption time

Abstract

The effect of different growth interruption time on the surface morphology and optical properties of InGaN quantum dots (QDs) grown on 2-inch silicon substrates is investigated. The surface becomes rougher and the photoluminescence intensity has been enhanced significantly when employing the growth interruption method. Temperature-dependent photoluminescence and excitation powerdependent photoluminescence both present unchanged peak energy and line-width of QDs. The sharp increase of PL intensity in medium temperature regime is attributed to the fingerprint of the existence of InGaN QDs. The shape of the QDs are further confirmed by the transmission electron microscopy with a size of 3 nm by 4 nm. Among the samples, a growth interruption time of 30 s gives the best optical performance.

Realizing Single Chip White Light InGaN LED via Dual-Wavelength Multiple Quantum Wells

“…The PL integral intensity changing with excitation power obeys a power law function, viz. , where I is the PL integral intensity, P is the excitation power and m is the index [ 18 , 30 , 31 ]. The fitted results are demonstrated in Figure 3 b.…”

Investigation of Micromorphology and Carrier Recombination Dynamics for InGaN/GaN Multi-Quantum Dots Grown by Molecular Beam Epitaxy

“…In order to further explore the relaxation and recombination mechanism of carriers in QDs, TRPL measurements were performed at different temperatures with an excitation power of 1 mW. Figure 7a shows the TRPL decay curves at different temperatures from 10 K to 300 K. All decay curves are well fitted with a two-componential exponential function as followed [18]:…”

“…The studies about the growth of InGaN QDs grown by MBE are not systematical, even though unique advantages in the growth of low low-dimensional materials. Moreover, in spite of a few reports [17][18][19] on the luminescence mechanism of InGaN QDs, further studies are required for the intrinsic relation between microstructure with optical properties, as well as carrier dynamics [20,21].…”

III-Nitride Materials: Properties, Growth, and Applications

“…In addition, the light emission mechanisms of InGaN have also been investigated through the clarification of localized states [10] and the direct observation of carrier transportation between different localized states [11,12]. Some mechanisms still need to be unveiled, such as the abnormal enhancement of photoluminescence (PL) intensity in the mid-temperature range of InGaN materials during the temperature-dependent photoluminescence (TDPL) measurement [13][14][15][16][17][18].…”