The non-stoichiometric HgCdTe evaporation during the surface processing will lead to surface defects thus requiring chemical passivation.
I think that you may obtain information in this paper : http://proceedings.spiedigitallibrary.org/proceeding.aspx?articleid=1380513
Dear Shiva you may use Spin-On Glass Coatings. Silicon dioxide is a proper material for passivating and protecting surfaces. This material is used intensively in silicon technology and I estimate that it could be used for ii-vi compound.This material is available in the market and it is applied on the surface using spinners. I hope it worksI wish you success.
One of the best ways for HgCdTe passivation is the electrochemical deposition of CdS. See my papers Surf. Interface Anal. 22 (1994) 197, Mater. Sci. Eng. B 28 (1994) 43 and references therein.
In early work with HgCdTe we showed that passivation with SiO2 was possible with a proprietary process; P. Morgen et. al. J. Vac. Sci. Technol. 21, 161 (1982).
Thank you PER MORGEN for proving my estimation that silicon dioxide is a proper passivization material.
A simple way to make a hard SiO2 glass coating on it is to submerge into a high Na/Si ratio sodium silicate solution; create silica gel from it by appropriately changing the pH with dilute HCl or NaOH solution; remove its water content by some heating (you can also use vacuum) and by gradually increasing the temperature calcine it at around 550 oC. You will get a molten glass sheet around your sample.
Thank you all for great feedback. This is what we did.
1. Prepared test 3D structures on HgCdTe
2. Spin-on SiO2, annealed at 250C in nitrogen
3. Checked electrical insulation.
However, the device leakage properties are not that great. Is there a way to address the problem?
Dear Shiva can you describe your test structure in detail to see the cause of leakage.
Did you measure the device performance before passivation? It is advisable to measure the device before and after passivation to localize the leakage and to isolate the effect of the passivation layer.
Wish you success.
zekry
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