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    Review of 'Marrying Medicine and Materials: Artemisinin (Qinghaosu) Particle is Soft Enough for Scratching Hard SiC Wafer in Water'

    Marrying Medicine and Materials: Artemisinin (Qinghaosu) Particle is Soft Enough for Scratching Hard SiC Wafer in WaterCrossref
    Average rating:
        Rated 4.5 of 5.
    Level of importance:
        Rated 5 of 5.
    Level of validity:
        Rated 4 of 5.
    Level of completeness:
        Rated 4 of 5.
    Level of comprehensibility:
        Rated 5 of 5.
    Competing interests:

    Reviewed article

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    • Abstract: found
    • Article: found
    Is Open Access

    Marrying Medicine and Materials: Artemisinin (Qinghaosu) Particle is Soft Enough for Scratching Hard SiC Wafer in Water

    Silicon carbide (SiC) single crystals, along with sapphire and silicon, are one of most important substrates for high-brightness LED fabrications. Owing to extremely high hardness (Mohs’ scale of 9.5) and chemical inertness, the polishing rate of SiC with conventional chemical mechanical polishing (CMP) methods is not high, and surface scratches are also inevitable because of using slurry containing hard abrasives such as silica particles. Here artemisinin (Qinghaosu) crystals, very soft molecular solids, were found, for the first time to the best of our knowledge, to effectively polish SiC wafers even in pure water as demonstrated by proof-of-concept scratching experiments using atomic force microscopy (AFM). The underlying mechanism is attributed to activated oxidation of SiC by mechanically released reactive ·OH free radicals from the endoperoxide bridges. The preliminary results reported here have important implications for developing novel alternative green and scratch-free polishing methods for hard-brittle substrates including SiC and others.

      Review information

      This work has been published open access under Creative Commons Attribution License CC BY 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Conditions, terms of use and publishing policy can be found at www.scienceopen.com.

      chemical mechanical polishing,Silicon carbide,oxidation,atomic force microscopy,artemisinin,hydroxyl free radical

      Review text

      This manuscript describes an interesting method for effectively polishing SiC wafers using antimalarial drug artemisinin. The polishing mechanism discussed in this proof-of-concept demonstration would have important implications for developing novel polishing methods. Overall this work is logically pursued and the manuscript is well written. However, I have some concerns regarding the research work as listed below:

      1. The equation in Figure 3: 2SiC + 4OH·+3O2 → 2SiC32– +4H+ + 2CO2 should be corrected to

      2SiC + 4OH·+3O2 → 2SiO32– +4H+ + 2CO2.

      2. Figure 2c should be marked in Text in Page 3 for clarity.

      3. In paragraph 1 Page 4, the authors should provide some references to explain the relationship between melting point and hardness, before concluded that artemisinin crystals have lower hardness compared with other common abrasives.


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