Gridchin Vladislav O, Kotlyar Konstantin P, Reznik Rodion R, Dragunova Anna S, Kryzhanovskaya Natalia V, Lendyashova Vera V, Kirilenko Demid A, Soshnikov Ilya P, Shevchuk Dmitrii S, Cirlin George G
Alferov University, Saint-Petersburg 194021, Russia.
Saint-Petersburg State University, Saint-Petersburg 198504, Russia.
Nanotechnology. 2021 May 28;32(33). doi: 10.1088/1361-6528/ac0027.
InGaN nanostructures are among the most promising candidates for visible solid-state lighting and renewable energy sources. To date, there is still a lack of information about the influence of the growth conditions on the physical properties of these nanostructures. Here, we extend the study of InGaN nanowires growth directly on Si substrates by plasma-assisted molecular beam epitaxy. The results of the study showed that under appropriate growth conditions a change in the growth temperature of just 10 °C leads to a significant change in the structural and optical properties of the nanowires. InGaN nanowires with the areas containing 4%-10% of In with increasing tendency towards the top are formed at the growth temperature of 665 °C, while at the growth temperatures range of 655 °C-660 °C the spontaneously core-shell NWs are typically presented. In the latter case, the In contents in the core and the shell are about an order of magnitude different (e.g. 35% and 4% for 655 °C, respectively). The photoluminescence study of the NWs demonstrates a shift in the spectra from blue to orange in accordance with an increase of In content. Based on these results, a novel approach to the monolithic growth of InGaN NWs with multi-colour light emission on Si substrates by setting a temperature gradient over the substrate surface is proposed.
氮化铟镓纳米结构是用于固态可见光照明和可再生能源最具潜力的候选材料之一。到目前为止，关于生长条件对这些纳米结构物理性质的影响仍缺乏相关信息。在此，我们通过等离子体辅助分子束外延技术扩展了对直接在硅衬底上生长氮化铟镓纳米线的研究。研究结果表明，在适当的生长条件下，生长温度仅变化10°C就会导致纳米线的结构和光学性质发生显著变化。在665°C的生长温度下形成了顶部含铟量为4%-10%且呈增加趋势的氮化铟镓纳米线，而在655°C-660°C的生长温度范围内通常会出现自发形成的核壳纳米线。在后一种情况下，核和壳中的铟含量相差约一个数量级（例如，在655°C时分别为35%和4%）。对纳米线的光致发光研究表明，随着铟含量的增加，光谱从蓝色向橙色移动。基于这些结果，提出了一种通过在衬底表面设置温度梯度在硅衬底上实现具有多色发光的氮化铟镓纳米线单片生长的新方法。
