As per available literature, amorphous structure of silicon is unstable and can be converted to crystalline by annealing at low temperature e.g. 100 C for 10 minutes but the reverse activity could not found in literature.
I am intended to make the crystalline structure of silicon (e.g wafer) to amorphous. Can anyone guide me or give me a idea to change it ?
Here is an example of successful amorphization of crystalline silicon based on using femtosecond laser irradiation and wet chemical etching.
Low temperature ion irradiation (RT) might result in disordering leading amorphization. This would require a higher ion dose, so try heavy ion irradiation, such as Kr, to get higher doses in shorter times. Keep the irradiation temperature well below the recrystallization temperature of Si.
You can ion implant with Si. Most (insufficiently hot) implantation processes lead to amorphisation and implanting with the same element means you get amorphisation only.
you Can the crystalline silicon be converted to amorphous structure by change the surface of Si wafer to porous surface I think porous silicon like amorphous silicon
@ Sha Anwer Kakil
I don't want to go for porous silicon and I don't think so that porous silicon is amorphous.
In the TEM preparation (thinning, cleaning ...) of silicon is obtained always amorphization of the surface. By FIB is this strong pronounced than in case of an argon-ion source. See for instance:
Roediger, P. , Wanzenboeck, H.D. , Waid, S., Hochleitner, G., Bertagnolli, E.: Focused-ion-beam-inflicted surface amorphization and gallium implantation-new insights and removal by focused-electron-beam-induced etching, Nanotechnology Volume 22, Issue 23, 10 June 2011, Article number 235302
Use this link if you have free access:
http://iopscience.iop.org/0957-4484/22/23/235302/pdf/0957-4484_22_23_235302.pdf
The transformation of silicon to the amorphous state by implanted ions was studied both experimentally and theoretically... For all implants, the first ion created only predamage, while the second or third ion into the same region caused the amorphous transformation. The critical‐energy‐density model was in good agreement with the measured critical doses. This model assumed that a region would become amorphous if the energy density deposited into atomic processes by the ions exceeded the critical energy density of 6×1023 eV/cm3. For high‐temperature implantations, out‐diffusion models can explain the temperature dependence of the critical dose. Although the analysis is not completely definitive, the critical‐energy‐density model may also be valid at high temperature if diffusion of the damage energy is taken into account. This out‐diffusion of energy from around the ion track occurs via a thermally activated process. Probably, the energy moves with the out‐diffusion of the vacancies from the ion track.
I have feeling that Ion beam method will make only a shallow surface thickness amorphous. Also this process does not seems to be continuous or in other words cannot be performed at large scale.
If we take this problem with another angle and aimed to make the complete crystal structure disordered then what should we do? What energy is required to make the said structure distorted? Is there any other way to supply this energy to the Silicon system?
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