| Autor: |
Raphael, Johanna, Kujofsa, Tedi, Ayers, J. E. |
| Předmět: |
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| Zdroj: |
International Journal of High Speed Electronics & Systems; Mar-Dec2020, Vol. 29 Issue 1-4, pN.PAG-N.PAG, 6p |
| Abstrakt: |
Metamorphic semiconductor devices often utilize compositionally-graded buffer layers for the accommodation of the lattice mismatch with controlled threading dislocation density and residual strain. Linear or step-graded buffers have been used extensively in these applications, but there are indications that sublinear, superlinear, S-graded, or overshoot graded structures could offer advantages in the control of defect densities. In this work we compare linear, step-graded, and nonlinear grading approaches in terms of the resulting strain and dislocations density profiles using a state-of-the-art model for strain relaxation and dislocation dynamics. We find that sublinear grading results in lower surface dislocation densities than either linear or superlinear grading approaches. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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