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

窄禁带半导体合金&lt;Hg_（1-x）&gt; <Mn_x>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半导体&lt;Hg_（1-x）&gt; Te相似的性质<Cd_x>外，还是一种典型的半磁半导体。在本项目中，我们成功地从富汞溶液中通过液相外延（LPE）生长出了高质量的晶体。这可以通过一种特殊的封闭系统方法来实现，该方法使用密封安瓿设置在可旋转的炉中。用<Mn_x>几种新的方法对用上述方法生长的&lt;Hg_（1-x）&gt; Te进行了表征，并与&lt;Hg_（1-x）&gt; Te作了比较<Cd_x>。特别是利用强磁场的新方法被证实是非常有用的载流子复合过程，在半导体传感器中具有至关重要的特性。此外，载流子复合过程和晶体质量之间的关系已被澄清，其中晶体质量已被许多技术评估，包括Ratherford背散射技术，使用高能重离子，特别适用于Hg、Te等重原子组成的化合物材料。

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.