Semiconductor materials with disorder: Materials issues and device implications

半导体是存在于电子器件内的有源电子材料。通过对此类器件中使用的半导体的材料特性的深入理解，电子学取得了很大的进步。已知无序在形成这些性质中起重要作用。非晶半导体在原子的基本分布中表现出无序，即，这些材料中的原子不以其晶体对应物的有序和周期性方式分布。在非晶格匹配衬底上生长为外延膜的半导体，例如在蓝宝石上生长的氮化镓，也表现出一种无序形式，即，穿透位错线，其从下面的衬底延伸到半导体材料中。这些不同形式的无序影响这些半导体的材料性质。因此，无序有可能改变使用这种半导体制造的电子器件的性能。 拟议的研究计划旨在研究无序如何影响这些半导体的材料特性，并探索由此产生的器件影响。本研究计划将考虑两种类型的无序半导体：（1）制备为薄膜的非晶半导体，和（2）在非晶格匹配衬底上制备的外延半导体。这些薄膜层的光学响应将是我们考虑的非晶半导体相关的探索的主要焦点，而外延层分析将集中在这些材料内的线程位错线的占用。各种形式的紊乱以及紊乱在影响器械性能方面所起的作用是支撑这些研究工作的潜在主题。 这项研究将有助于促进加拿大电子工业的增长和发展，据一些人估计，到2012年，加拿大电子工业的全球销售额（每年）将超过1万亿美元。

Semiconductors are the active electronic materials present within electron devices. A great deal of progress in electronics has been achieved through a deep understanding of the material properties of the semiconductors used within such devices. Disorder is known to play an important role in shaping these properties. Amorphous semiconductors exhibit disorder in the underlying distribution of atoms, i.e., the atoms within these materials are not distributed in the ordered and periodic manner of their crystalline counterparts. Semiconductors that are grown as epitaxial films on non-lattice matched substrates, such as gallium nitride grown on sapphire, also exhibit a form of disorder, i.e., threading dislocation lines, which extend from the underlying substrate into the semiconductor material. These various forms of disorder impact upon the material properties of these semiconductors. Consequently, disorder has the potential to alter the performance of the electron devices that are fabricated using such semiconductors. The proposed research program aims to study how disorder impacts upon the material properties of these semiconductors and to explore the resultant device implications. Two types of disordered semiconductors will be considered in this research program: (1) amorphous semiconductors prepared as thin-films, and (2) epitaxial semiconductors prepared on non-lattice matched substrates. The optical response of these thin-film layers will be the primary focus of our explorations related to the amorphous semiconductors we consider, while the epitaxial layer analyses will focus on the occupancy of the threading dislocation lines within such materials. Disorder, in its various forms, and the role that disorder plays in influencing device performance, is the underlying theme underpinning these research endeavors. This research will help nurture the growth and development of the electronics industry here in Canada, an industry that has been estimated by some to have the potential to exceed $ 1 Trillion in sales worldwide (per annum) by the year 2012.