Liquid Phase Epitaxial Growth and Characterization of New Semiconductor Alloys for Infrared Sensors

窄禁带半导体合金&lt；Hg1-x&gt；&lt；Mnx&gt；Te有望成为一种新的红外探测器材料。这种合金除了具有与传统红外器件半导体&lt；Hg_(1-x)&gt；&lt；Cd_x&Gt；Te相似的性质外，还是一种典型的半像磁半导体。在这个项目中，我们成功地从富汞溶液中用LPE(液相外延)方法生长了高质量的晶体。这是用一种特殊的封闭系统方法，在可旋转的炉子中用密封的安瓶来实现的。用上述方法生长的&lt；Hg_(1-x)&gt；&lt；Mn_x&gt；Te用几种新的方法进行了表征，并与&lt；Hg_(1-x)&gt；&lt；Cd_x&gt；Te的情况进行了比较。特别是利用强磁场来表征半导体传感器中至关重要的载流子复合过程是非常有用的。此外，还阐明了载流子复合过程与晶体质量之间的关系，其中包括利用高能重离子的Ratherford背散射技术来评估晶体质量，该技术特别适用于由重原子组成的化合物，如汞和碲。

A narrow gap semiconductor alloy, <Hg_(1-x)> <Mn_x> Te is expected to be a new candidate for infrared detector materials. In addition to the fact that this alloy shows similar properties to the conventional infrared-device semiconductor <Hg_(1-x)> <Cd_x> Te, it is also a typical one of the so-called semimagnetic semiconductors. Thus it has a great variety of potential of being a material with some new function other than the conventional alloys.In this project, we have succeeded to grow high quality crystals by LPE (liquid phase epitaxy) from the Hg-rich solution. This is attainable by a special closed system method using a sealed ampule set in a rotatable furnace.<Hg_(1-x)> <Mn_x> Te grown by the above mentioned method has been characterized by several new method, comparing with the case of <Hg_(1-x)> <Cd_x> Te. Especially, a new method utilizing high magnetic field is confirmed to be very useful to characterize the carrier recombination processes which has an essential importance in the semiconductor sensors.Furthermore,a relation between the carrier recombination processes and the crystal quality has been clarified, where the crystal quality has been evaluated by many techniques including a Ratherford backscattering technique using energetic heavy ions, which is particularly suitable for the compound materials composed of heavy atoms such as Hg and Te.