Black germanium photodetector exceeds external quantum efficiency of 160%
In this work, a viable method is demonstrated to realize high-performance germanium (Ge) photodetectors (PDs) on the nanostructured Ge surface, namely black Ge, formed by chlorine (Cl2) gas-based reactive ion etching at room temperature. Black Ge surface has spike-like pyramidal structures with a wi...
| Main Authors: | , , , |
|---|---|
| Other Authors: | |
| Format: | Journal Article |
| Language: | English |
| Published: |
2022
|
| Subjects: | |
| Online Access: | https://hdl.handle.net/10356/156884 |
| _version_ | 1826116062815453184 |
|---|---|
| author | An, Shu Liao, Yikai Shin, Sang-Ho Kim, Munho |
| author2 | School of Electrical and Electronic Engineering |
| author_facet | School of Electrical and Electronic Engineering An, Shu Liao, Yikai Shin, Sang-Ho Kim, Munho |
| author_sort | An, Shu |
| collection | NTU |
| description | In this work, a viable method is demonstrated to realize high-performance germanium (Ge) photodetectors (PDs) on the nanostructured Ge surface, namely black Ge, formed by chlorine (Cl2) gas-based reactive ion etching at room temperature. Black Ge surface has spike-like pyramidal structures with a width and height up to 150 and 570 nm, respectively. Average reflection of black Ge is reduced to 2% at a wavelength range from 1 to 2 µm, while that of planar Ge is ≈37%. Light absorption is strongly enhanced by the significantly reduced reflection, thereby leading to an increase in responsivity of black Ge PDs. Moreover, external quantum efficiency (EQE) exceeds 160% at 1550 nm, indicating the existence of internal gain resulted from multiple carrier generation in Ge nanostructures. Therefore, this work provides an effective and reliable approach to significantly enhance photodetection performance of Ge-based optoelectronic devices. |
| first_indexed | 2024-10-01T04:05:17Z |
| format | Journal Article |
| id | ntu-10356/156884 |
| institution | Nanyang Technological University |
| language | English |
| last_indexed | 2024-10-01T04:05:17Z |
| publishDate | 2022 |
| record_format | dspace |
| spelling | ntu-10356/1568842022-04-26T06:46:37Z Black germanium photodetector exceeds external quantum efficiency of 160% An, Shu Liao, Yikai Shin, Sang-Ho Kim, Munho School of Electrical and Electronic Engineering Engineering::Electrical and electronic engineering Black Germanium Enhanced Responsivity In this work, a viable method is demonstrated to realize high-performance germanium (Ge) photodetectors (PDs) on the nanostructured Ge surface, namely black Ge, formed by chlorine (Cl2) gas-based reactive ion etching at room temperature. Black Ge surface has spike-like pyramidal structures with a width and height up to 150 and 570 nm, respectively. Average reflection of black Ge is reduced to 2% at a wavelength range from 1 to 2 µm, while that of planar Ge is ≈37%. Light absorption is strongly enhanced by the significantly reduced reflection, thereby leading to an increase in responsivity of black Ge PDs. Moreover, external quantum efficiency (EQE) exceeds 160% at 1550 nm, indicating the existence of internal gain resulted from multiple carrier generation in Ge nanostructures. Therefore, this work provides an effective and reliable approach to significantly enhance photodetection performance of Ge-based optoelectronic devices. Agency for Science, Technology and Research (A*STAR) Ministry of Education (MOE) Submitted/Accepted version This work was supported by the A*STAR Singapore, Advanced Manufacturing and Engineering (AME) Young Individual Research Grant (YIRG) under the project A2084c0066 and Ministry of Education Singapore, under the Grant ACRF Tier 2 grant (T2EP50120-0003). 2022-04-26T06:46:37Z 2022-04-26T06:46:37Z 2022 Journal Article An, S., Liao, Y., Shin, S. & Kim, M. (2022). Black germanium photodetector exceeds external quantum efficiency of 160%. Advanced Materials Technologies, 7(1), 2100912-. https://dx.doi.org/10.1002/admt.202100912 2365-709X https://hdl.handle.net/10356/156884 10.1002/admt.202100912 2-s2.0-85114894939 1 7 2100912 en A2084c0066 T2EP50120-0003 Advanced Materials Technologies This is the peer reviewed version of the following article: An, S., Liao, Y., Shin, S. & Kim, M. (2022). Black germanium photodetector exceeds external quantum efficiency of 160%. Advanced Materials Technologies, 7(1), 2100912-, which has been published in final form at Advanced Materials Technologies. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions. application/pdf |
| spellingShingle | Engineering::Electrical and electronic engineering Black Germanium Enhanced Responsivity An, Shu Liao, Yikai Shin, Sang-Ho Kim, Munho Black germanium photodetector exceeds external quantum efficiency of 160% |
| title | Black germanium photodetector exceeds external quantum efficiency of 160% |
| title_full | Black germanium photodetector exceeds external quantum efficiency of 160% |
| title_fullStr | Black germanium photodetector exceeds external quantum efficiency of 160% |
| title_full_unstemmed | Black germanium photodetector exceeds external quantum efficiency of 160% |
| title_short | Black germanium photodetector exceeds external quantum efficiency of 160% |
| title_sort | black germanium photodetector exceeds external quantum efficiency of 160 |
| topic | Engineering::Electrical and electronic engineering Black Germanium Enhanced Responsivity |
| url | https://hdl.handle.net/10356/156884 |
| work_keys_str_mv | AT anshu blackgermaniumphotodetectorexceedsexternalquantumefficiencyof160 AT liaoyikai blackgermaniumphotodetectorexceedsexternalquantumefficiencyof160 AT shinsangho blackgermaniumphotodetectorexceedsexternalquantumefficiencyof160 AT kimmunho blackgermaniumphotodetectorexceedsexternalquantumefficiencyof160 |