Semiconductor quantum dots (QDs) have been widely used in various optoelectronic devices. Extensive studies have been devoted to the application of Si QDs with the aim of realizing various optoelectronic functions based on the modified energy band structure in QDs compared with bulk crystals. Therefore, it is necessary to be able to directly probe the carrier dynamics in single Si QDs of nanoscale dimensions deposited on a SiO2/Si surface, where the environment is compatible with Si-based semiconductor devices. This letter reports the observation and comparison of the ultrafast electron dynamics just after the photoexcitation of isolated and clustered Si QDs on a SiO2/Si surface using time-resolved photoemission electron microscopy with spatial and temporal resolutions of 50 nm and 100 fs, respectively. The detailed structure of QDs was confirmed directly by scanning electron microscopy observations. The results obtained in the present study show that the carrier lifetime in isolated QDs is shorter than that in clustered QDs. This is consistent with the electron–hole interaction in nanospace, significantly modifying the carrier recombination rates.
Skip Nav Destination
CHORUS
Article navigation
29 July 2019
Research Article|
August 02 2019
Comparison of picosecond electron dynamics in isolated and clustered Si quantum dots deposited on a semiconductor surface
Keiki Fukumoto
;
Keiki Fukumoto
a)
1
High Energy Accelerator Research Organization (KEK)
, 1-1 Oho, Tsukuba, Ibaraki 305-0801 Japan
Search for other works by this author on:
Ayse Seyhan
;
Ayse Seyhan
b)
2
Niğde Omer Halisdemir University, Nanotechnology Application and Research Center
, 51240 Niğde, Turkey
Search for other works by this author on:
Ken Onda;
Ken Onda
3
Kyushu University
, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
Search for other works by this author on:
Shunri Oda
;
Shunri Oda
4
Tokyo Institute of Technology
, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8550, Japan
Search for other works by this author on:
Shin-ya Koshihara
Shin-ya Koshihara
4
Tokyo Institute of Technology
, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8550, Japan
Search for other works by this author on:
Appl. Phys. Lett. 115, 053105 (2019)
Article history
Received:
March 26 2019
Accepted:
July 07 2019
Citation
Keiki Fukumoto, Ayse Seyhan, Ken Onda, Shunri Oda, Shin-ya Koshihara; Comparison of picosecond electron dynamics in isolated and clustered Si quantum dots deposited on a semiconductor surface. Appl. Phys. Lett. 29 July 2019; 115 (5): 053105. https://doi.org/10.1063/1.5097611
Download citation file:
Sign in
Don't already have an account? Register
Sign In
You could not be signed in. Please check your credentials and make sure you have an active account and try again.
Could not validate captcha. Please try again.
Sign in via your Institution
Sign in via your InstitutionPay-Per-View Access
$40.00