Ramakrishna Madaka

14 Questions 19 Answers 0 Followers

Questions related from Ramakrishna Madaka

What is the significance of 'dark spectral response'?

Can anyone explain me the significance of ''dark spectral response'' or " Dark EQE" of solar cell and how it will help to improve the efficiency of solar cell?

04 April 2019 8,007 7 View

What is the difference between the Granular growth and Columnar growth?

what is the main difference between the growth mechanism of Granular and Columnar growth in microcrystalline silicon thin films?

05 May 2016 9,900 0 View

How can I create periodic texture on flexible substructures like polyimide (PI), PET?

I would like to create periodic texture structure on flexible substrates like Polyimide (PI), polyethylene terephthalate (PET) for multiple reflections of light. Can anyone suggest, how can I...

03 March 2015 7,001 6 View

In a-Si:H, are dandling bond defects present in thermal equilibrium conditions in the material identical to DB defects formed by optical degradation?

See above

08 August 2014 9,560 3 View

Can someone tell me how to etch polyimide substrate (Kapton) and will it dissolve in any solution?

I have this amorphous silicon, a-Si:H, film I want etch it from polyimide and I want to know how to approach it.

07 July 2014 3,858 7 View

Why defect density of states have Gaussian distribution in a-Si:H?

In hydrogenated amorphous silicon why density of defect states following Gaussian distribution function and band tails are exponential distribution?

04 April 2014 9,929 5 View

What is the exact difference between photoelectric effect and photovoltaic effect?

In both cases electrons are ejected from the outer shell. Can anyone give me a clear explanation of the differences between the two?

04 April 2014 6,412 10 View

Why are band tails exponential nature in amorphous materials?

In crystalline materials the conduction band (C.B) and valence band (V.B) are parabolic nature and has a sharp mobility edges. In amorphous case the sharp edge disappears because of defects but it...

03 March 2014 5,619 7 View

How does silane flow rate depend on the thickness of the sample?

I have deposited a-Si:H films by PECVD, as increasing the silane flow rate (SFR) & process pressure(PP), the thickness of sample decreases upto certain SFR& PP, again thickness increased as...

03 March 2014 1,930 0 View

Up to which temperature can we continue to anneal?

If I deposited amorphous silicon film, the substrate temperature is120°C on polyimide, PET or Corning glass then can we anneal at 120°C for a temperature dependent electrical conductivity (I-V)...

01 January 2014 3,804 6 View

How does current density vary with respect to i-layer thickness?

I have read one journal where it states that with the thickness of the i-layer (0.5, 0.8,1, 2, 2.5 microns), the current density initially increases up to 1 micron and gets saturated. What is the...

01 January 2014 3,536 4 View

Why must the TCO layer be thicker?

In N-I-P or P-I-N single junction solar cells, top and bottom TCO should be thicker in comparison to N-I-P individual layers. Is there any additional reason for this except surface diffusion?

11 November 2013 9,413 1 View

Which one is the correct way to find out band gap from UV-Vis?

Band gap finding from UV-Visible data. Some people are using Y-axis as (α*hν)^1/2 and some people are using α^2 instead, i.e. α is function of hν .α(hν). X-axis is same hν (eV).

05 May 2013 8,836 6 View

How can we find point and space group determination by using TEM?

Plz explain briefly ..

10 October 2012 6,247 5 View