Research on Fast Detection Technology of Dark Currents in a Ge–Si Detector Array
, Xuetong Li 1, Junfeng Song 1,2, Zijian Liu 1, Ziming Wang 1 and Chengming Li 1
Preeta Sharan
Round 1
Reviewer 1 Report
The authors present a pin-Photodetector array and a system to analyze the dark current of such an array. While the conducted research is interesting, important background, scientific analysis and measurements are missing. While the authors discussed a number of APD arrays etc., the do not discuss state-of-the-art pin-PD arrays and metrics of such. The second missing part is the discussion of state-of-the-art detection systems if such exist or the need of theor existence. Wile the authors claim that the dark current is inversely proportional to the optical performance it is necessary to demonstrate the dependence of their measurement results and e.g. the responsivity, which could be measured with low speed. Because of this, I recommend a rejection of the paper, because complete new experiments and a reorganisation of the manuscript is needed.
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Reviewer 2 Report
The study has proven to be highly effective, particularly evident in the scanning test results, which indicate that the dark current is within the nanampere level and the proportion of defective points is below 1%. However, the reviewer suggests that the authors should include a new section in the report, highlighting the essential recommendations derived from the study.
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Reviewer 3 Report
Thank you for your good study and I am happy to suggest publishing it after some corrections as below:
- Can you please clearly highlight the real novelty of your study in the abstract? Also, may you make a good comparison between your study ad the previously reported studies. It is better to summarize it in a table in the introduction or by the end of the manuscript.
- What do you think about the LiDAR applications based on MoO3, May this study help
Materials | Free Full-Text | Thermionic Emission of Atomic Layer Deposited MoO3/Si UV Photodetectors (mdpi.com)
Also the future of 2D materials si=uch as MoS2, Graphene
- I see also that the dark current is based on the thermionic emissions and temperatures, (refer to the mentioned paper )
- What is the breakdown voltage in Fig 2
- Fig 7, can you keep it in English for making easier for public
- Fig 8 (d), please take another photo,
- Since you have both simulation and experimental demonstrations Can you mention the experimental preparations section
- What is the potential applicability of using your device as a self-power photodetector device Self-powered perovskite photon-counting detectors | Nature
i see that the English has to rechecked again
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Reviewer 4 Report
The authors designed and manufactured a Ge-Si photodetector array and evaluated its dark current detection system with fast scanning characteristics. This study is an important work for the development process of future Ge-Si‑based Lidar optical receiver.
Questions:
1. Figure 9: authors mention that the experimentally measured data is completely consistent with the theoretical curve in Figure 2, obtained from eq. 1-4. The authors should list the values of the parameters in these equations used for calculating the dark current bias voltage curve.
2. The dark current of certain bad pixels is some uAmps. Does this cause reversible or permanent damage to the array? Can you detect and disable damaged pixels in real-time, and is there a need for this?
3. Device B shows the largest number of damaged pixels, which doesn’t follow the general trend. Do you have any insight into the causes? Is this a defective fabrication process? Have you tried to repeat the manufacturing and testing of this device?
4. What are your recommendations for the subsequent development of a LiDAR prototype system (pixel size, electronics configuration etc)?
Minor comments:
1. Page 2: give definitions for APD and DBR at the first mention.
2. End of page 2: what exactly do the authors mean by this sentence? “Based on the characteristic that the dark current of the detector is inversely proportional to its optical response characteristics, the performance of the detector is judged by comparing the magnitude of the dark current.”
3. Page 4, eq. (3): define ħ.
4. Page 9, last paragraph: authors say that they measure dark current in a range from -350mV to 500mV, but Fig 9 displays values at -3500mV to ~100mV. Please correct or explain the discrepancy.
5. Figure 9: is this curve for one pixel (first column, first row) or the whole array combined? Please clarify in the text and/or figure caption.
6. Figure 10(d) – wrong figure, i.e., both (d) and (e) show -0.5V data.
7. Page 8: alongside array area, authors could mention individual pixel area. Also, what is the fill factor (active area / pixel area)?
8. Figure 11: since data on this plot represents average dark current, it would be beneficial to add error bars or make a box plot.
Minor English editing may be required.
Repetitive "Can be used for..." in the introduction.
Consider splitting sentences instead of using semicolon.
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Reviewer 5 Report
REVIEWS OF THE PAPER
1. Equations are properly numbered but they are to be written using suitable equation tool. 2. In Fig. 10(d), and (e) the bias voltage is repeated as -0.5 V. So, In Fig. 10(d) the bias voltage should be -1.0V. 3. Analysis on Dark Currents on Fast DetectionTechnologyis awesome using the Ge-Si Semiconductor material. 4. All the specifications of Voltage follower, Amplification Circuit is specified correctly. 5. Various tests like Array Test and Data Analysis is performed which is very much essential for practical applications to determine maximum tolerance limits. 6. The readings in the table gives the clear analysis of Average Dark Current, Number of Pixcels and in turn Responsiveness which is the most important parameter. 7. The author has not mentioned about the drawbacks as well as the future scope, if these two parameters are included, may be, the work can be carried over by another researcher for better results. 8. The final conclusion of the paper goes like this that the paper can be accepted for the publication but with the above specified minor corrections. 9. The write up of the whole paper is very well organized and analysis is done at greater depth.Minor change s
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Round 2
Reviewer 1 Report
The background on detection systems is still lacking comparable detection systems. Furthermore I am still missing a clear goal of the conducted research. It is not clear if the manuscript focuses on the detection system or PD arrays. The experimental result of the dark current of the arrays is not put into connection with other results. Therefore I recommend a revision.
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Reviewer 3 Report
Thank you for your report
It might be revised one more time
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Round 3
Reviewer 1 Report
The paper is not substantially changed. Therefore I recommend a rejection of the paper.
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