Characterization of Structural Defects in (Cd,Zn)Te Crystals Grown by the Travelling Heater Method
, Lutz Kirste 4, Merve Pinar. Kabukcuoglu 5,6, Elias Hamann 5, Angelica Cecilia 5 and Michael Fiederle 1Round 1
Reviewer 1 Report
The authors conducted experimental on CZT crystals grown at different conditions; they provided very detailed analysis along characterization results: the compositional homogeneity, the resistivity, the extended defects and the resulting stress of these terrestrial crystals.
The work here not only provided correlation of the observed defects and growth parameters, but also shed light on approaches to further improve the crystal quality. I find these are important, and recommend to publish after addressing a few comments below:
- Page 1: could authors provide more illustration about the THM?
- Could authors provide more specific applications of CdZnTe Crystals based Radiation Detector ? This would help highlights the importance and meaning of this research…
- Page 2: though referred to a reference [14], could authors provide more key parameters on the experimental ? Temperature or other parameters of the territorial conditions?
- How long did it take to grow the crystals slabs in figure 1? How repeatable are the results?
- Section “3 Results” – line120: not sure about the color difference? could authors explain a bit more ?
- Line 121: what are the dimensions of the original seed ? Width and thickness?
- Figure 1: based on the optical photograph of the two slabs, (a) and (b) appeared different color: One seems blue why one seems grey ? Could authors explain ?
Author Response
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Author Response File: 
Author Response.pdf
Reviewer 2 Report
In this work the compositional homogeneity, structural defects and resistivity of two (Cd,Zn)Te (CZT) crystals grown by the Travelling Heater Method (THM ) from ground experiments were investigated.To determine the chemical composition of the crystals, Energy Dispersive X-ray Analysis (EDX) was applied. Additionally, the orientations and compositions of the seed interface and grown crystal were determined by High-Resolution X-ray Diffractometry (HRXRD). According to the results of HRXRD and EDX, the authors observed a change in the ZnTe content at the seed/grown crystal interface. It has been shown that according to birefringence and WBXDT images, this ZnTe change causes a strong local stress associated with extensive deformation microstructures in this region, especially dislocation networks that propagate forward into the grown crystal. It has been shown that according to birefringence and X-ray White Beam Topography images, this ZnTe change causes a strong local stress associated with extensive deformation microstructures in this region, especially dislocation networks that propagate forward into the grown crystal. By adjusting the growth parameters, the ZnTe variations and the resulting stress were efficiently reduced. In addition, it was revealed that large inclusions and grain boundaries can generate high degree of stress, leading to the formation of dislocation slip bands and subgrain boundaries. It has been shown that dominant defects, including grain boundaries, dislocation networks and cracks inside crystals, lead to changes in the resistivity in crystals.
In general, the work leaves a pleasant impression due to the detail and thoroughness of the presentation of the results obtained, and undoubtedly deserves to be published in the journal Crystals.
There is one remark concerning the abundance of abbreviations, which makes it difficult for the reader to understand the essence of the results obtained. For example, in conclusion, the authors use the abbreviation “WBXDT images”, which is absent in the text.
Comments for author File: 
Comments.docx
Author Response
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Author Response File: Author Response.pdf
