Effects of pressure on atomic and electronic structure and crystallization dynamics of amorphous Ge2Sb2Te5

被引：30

作者：

Im, Jino ^{[1
]}

Cho, Eunae ^{[2
]}

Kim, Dohyung ^{[3
]}

Horii, Hideki ^{[3
]}

Ihm, Jisoon ^{[1
]}

Han, Seungwu ^{[2
]}

机构：

[1] Seoul Natl Univ, Dept Phys & Astron, Seoul 143747, South Korea

[2] Seoul Natl Univ, Dept Mat Sci & Engn, Seoul 151744, South Korea

[3] Samsung Elect, Semicond Business, Proc Dev Team, Memory R&D Ctr, Yongin 44671, South Korea

来源：

PHYSICAL REVIEW B | 2010年 / 81卷 / 24期

关键词：

FILMS;

D O I：

10.1103/PhysRevB.81.245211

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

We investigate the effects of pressure on atomic and electronic structures of amorphous Ge2Sb2Te5 using first-principles methods. The supercell volume is varied from 0.94 to 1.13 times the nominal amorphous volume in melt-quench simulations. When the simulation cell is compressed, we find that the energy gap is reduced and the number of localized in-gap states is increased. These results indicate that pressurized amorphous Ge2Sb2Te5 exhibits better conduction than Ge2Sb2Te5 formed under stress-free conditions. We also find that the positive pressure increases the densities of fourfold rings in amorphous Ge2Sb2Te5, shifting the local order toward the crystalline phase. Consistently, fast crystallization is identified for compressed amorphous Ge2Sb2Te5.

引用

页数：5

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