Title: Pit rim decomposition into multiple quantum dots on surfaces of epitaxial thin films grown on pit-patterned substrates

Abstract

We report results of dynamical simulations according to an experimentally validated surface morphological evolution model on the formation of regular arrays of quantum dot molecules (QDMs) consisting of 1D arrays of smaller interacting quantum dots (QDs). These QD arrays form along the sides of each pit rim on the surface of a coherently strained thin film epitaxially deposited on a semiconductor substrate, the surface of which consists of a periodic pattern of inverted prismatic pits with rectangular pit openings. We find that this complex QDM pattern results from the decomposition of the pit rim from a “quantum fortress” with four elongated QDs into four 1D arrays of multiple smaller QDs arranged along each side of the pit rim. Systematic parametric analysis indicates that varying the pit opening dimensions and the pit wall inclination directly impacts the number of QDs in the resulting QDM pattern, while varying the pit depth only affects the dimensions of the QDs in the nanostructure pattern. Therefore, the number, arrangement, and sizes of QDs in the resulting pattern of QDMs on the film surface can be engineered precisely by proper tuning of the pit design parameters. Our simulation results are supported by predictions of morphological stabilitymore » analysis, which explains the pit rim decomposition into multiple QDs as the outcome of a tip-splitting instability and provides a fundamental characterization of the post-instability nanostructure pattern. Our theoretical findings can play a vital role in designing optimal semiconductor surface patterns toward enabling future nanofabrication technologies.« less

Authors:

Patel, Omeet N.  ^[1];

• Search DOE PAGES for author "Patel, Omeet N."
• Search DOE PAGES for ORCID "0000-0002-0059-8351"

Chen, Chao-Shou  ^[1];

• Search DOE PAGES for author "Chen, Chao-Shou"
• Search DOE PAGES for ORCID "0000-0003-0791-0042"

Maroudas, Dimitrios  ^[1]

• Search DOE PAGES for author "Maroudas, Dimitrios"
• Search DOE PAGES for ORCID "0000-0001-9297-8839"

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+ Show Author Affiliations

1. Univ. of Massachusetts, Amherst, MA (United States)

Publication Date:

Thu Aug 25 00:00:00 EDT 2022

Research Org.:

Univ. of Massachusetts, Amherst, MA (United States)

Sponsoring Org.:

USDOE Office of Science (SC), Basic Energy Sciences (BES). Materials Sciences & Engineering Division; USDOE Office of Science (SC), Advanced Scientific Computing Research (ASCR). Scientific Discovery through Advanced Computing (SciDAC)

OSTI Identifier:

1902691

Alternate Identifier(s):

OSTI ID: 1883639

Grant/Contract Number:  

FG02-07ER46407; SC0018421

Resource Type:

Accepted Manuscript

Journal Name:

Journal of Applied Physics

Additional Journal Information:

Journal Volume: 132; Journal Issue: 8; Journal ID: ISSN 0021-8979

Publisher:

American Institute of Physics (AIP)

Country of Publication:

United States

Language:

English

Subject:

70 PLASMA PHYSICS AND FUSION TECHNOLOGY; 36 MATERIALS SCIENCE; Semiconductor device fabrication; Thin films; Nanofabrication; Linear stability analysis; Epitaxy; Quantum dots; Mass diffusivity; Computer simulation; Surface morphology; Semiconductor materials