Development of an epitaxial lift-off technique for II-VI semiconductor heterostructures

II-VI族半导体异质结构外延剥离技术的开发

基本信息

批准号：
EP/E02209X/1
负责人：
Kevin Prior
金额：
$ 12.95万
依托单位：
Heriot-Watt University
依托单位国家：
英国
项目类别：
Research Grant
财政年份：
2006
资助国家：
英国
起止时间：
2006 至无数据
项目状态：
已结题

来源：
https://gtr.ukri.org/projects?ref=EP%2FE02209X%2F1
关键词：
Development epitaxial lift off technique

项目摘要

II-VI semiconductors have many properties which are different from their III-V counterparts. One important property is the exciton binding energy which is much larger in II-VI compounds such as ZnSe and CdSe and can be increased still further by suitable confinement. This means that in ZnSe and CdSe excitons can be studied at room temperature or at high densities where complexes such as biexcitons can be observed. However, to study these phenomena in wide bandgap II-VI compounds requires an even wider bandgap barrier material. MgS is such a material and can be grown with low strain on GaAs in combination with ZnSe and CdSe. MgS is not an easy material to produce. The growth of this material was pioneered at Heriot-Watt and currently, we are one of only three labs worldwide where such MgS containing structures can be grown.We recently found that MgS has one other useful advantage, which is that weak acid can be used to dissolve it, separating the structure grown on top of it from the unwanted substrate underneath. This technique, called epitaxial lift-off, is a very powerful method of generating layers which can then be studied or subject to further processing. For example, the layers can easily be incorporated into optical cavities or placed on to a substrate with completely different physical properties.Unfortunately, this technique means that we can not use MgS as a barrier layer in the same structure. Recently, we have recently found that adding a small amount of zinc to MgS creates an alloy which has good confinement and resists the acid etching solution. This alloy has a large strain to GaAs, but it suggests that there are other related low strain alloys which would be entirely compatible with the structures we currently grow.In this study we aim to find the most suitable wide bandgap alloy composition which we can use which resists our etching solution. We will then demonstrate its use in semiconductor structures in combination with MgS, where the MgS allows us to perform epitaxial lift-off and the new alloy resists the etching and gives the confinement.

II-VI 族半导体具有许多不同于 III-V 族半导体的特性。一个重要的特性是激子结合能，它在 II-VI 族化合物（如 ZnSe 和 CdSe）中要大得多，并且可以通过适当的限制进一步增加。这意味着可以在室温或高密度下研究 ZnSe 和 CdSe 激子，其中可以观察到双激子等复合物。然而，要研究宽带隙 II-VI 化合物中的这些现象，需要更宽的带隙势垒材料。 MgS 就是这样一种材料，可以在 GaAs 上与 ZnSe 和 CdSe 结合以低应变生长。 MgS 不是一种容易生产的材料。这种材料的生长是赫瑞瓦特公司首创的，目前，我们是全球仅有的三个可以生长此类含 MgS 结构的实验室之一。我们最近发现 MgS 还有另一个有用的优势，即可以使用弱酸溶解它，将其顶部生长的结构与下面不需要的基材分开。这种技术称为外延剥离，是一种非常强大的生成层的方法，然后可以对其进行研究或进行进一步处理。例如，这些层可以很容易地合并到光学腔中或放置在具有完全不同物理特性的基板上。不幸的是，这种技术意味着我们不能在同一结构中使用 MgS 作为阻挡层。最近，我们发现在MgS中添加少量的锌可以产生一种具有良好限制性并能抵抗酸性蚀刻溶液的合金。这种合金对 GaAs 具有很大的应变，但这表明还有其他相关的低应变合金与我们目前生长的结构完全兼容。在这项研究中，我们的目标是找到我们可以使用的最合适的宽带隙合金成分它能抵抗我们的蚀刻溶液。然后，我们将展示其与 MgS 结合在半导体结构中的用途，其中 MgS 允许我们执行外延剥离，而新合金可以抵抗蚀刻并提供限制。