Oxidization of III-V Materials

[jarodparker198]

Hello,

In the framework of an academic study, I am reviewing the oxidation methods of III-V materials for optronic applications.

What are the best techniques to oxidize III-V materials such as InP, AsGa, or InSb in order to have a good quality oxide layer of about thirty nanometers? The oxide layer must be especially homogeneous and non-porous.

Thanks.

 

[ZapperZ]

Hello,

In the framework of an academic study, I am reviewing the oxidation methods of III-V materials for optronic applications.

What are the best techniques to oxidize III-V materials such as InP, AsGa, or InSb in order to have a good quality oxide layer of about thirty nanometers? The oxide layer must be especially homogeneous and non-porous.

Thanks.

Your question is rather vague, and I will tell you why.

First of all, what is the initial condition of these material? Were they freshly made, already in UHV? Or did you get them already sealed? Or were they already exposed to air?

Such information matters, because it will dictate what you are able to do, or not able to do, especially if you care that much about the oxide layer. If the material were freshly deposited, then using a leak valve to let in oxygen, followed by a series of post-oxidation studies to correlate oxygen flow, exposure time, sample heating temperature, etc... with oxide thickness and quality will determine what you need.

Zz.

 

[jarodparker198]

Your question is rather vague, and I will tell you why.

First of all, what is the initial condition of these material? Were they freshly made, already in UHV? Or did you get them already sealed? Or were they already exposed to air?

Such information matters, because it will dictate what you are able to do, or not able to do, especially if you care that much about the oxide layer. If the material were freshly deposited, then using a leak valve to let in oxygen, followed by a series of post-oxidation studies to correlate oxygen flow, exposure time, sample heating temperature, etc... with oxide thickness and quality will determine what you need.

Zz.

Hello Zz,

I thank you for your response.

To be more precise, I am not talking about deposited layers of III-V materials.
I am more talking about bulk materials like wafers of AsGa, InP or InSb.

What are the best techniques to oxidize the surface of wafers of III-V materials ?

 

[ZapperZ]

Hello Zz,

I thank you for your response.

To be more precise, I am not talking about deposited layers of III-V materials.
I am more talking about bulk materials like wafers of AsGa, InP or InSb.

What are the best techniques to oxidize the surface of wafers of III-V materials ?

If they are exposed to air, aren't they already oxidized?

GaAs or InSb that you get that way does NOT have the same quantum efficiency when compared to as-deposited films. So already the oxidation of the surface has changed at least one of its properties.

Zz.

 

[jarodparker198]

If they are exposed to air, aren't they already oxidized?

GaAs or InSb that you get that way does NOT have the same quantum efficiency when compared to as-deposited films. So already the oxidation of the surface has changed at least one of its properties.

Zz.

Yes you are probably right concerning the natural oxidation.

However I read in some papers that the natural oxide is chemically removed before the controlled oxidation of the substrate for further optronic applications.

The control of the oxide seems to be the major point, and that depends of the used technique

Regards,

 

[ZapperZ]

Yes you are probably right concerning the natural oxidation.

However I read in some papers that the natural oxide is chemically removed before the controlled oxidation of the substrate for further optronic applications.

The control of the oxide seems to be the major point, and that depends of the used technique

Regards,

Read my first response. That was why I asked the INITIAL state that they are in, and why I said that your description was vague. You didn't tell me this important part of the scenario, i.e. surface cleaning. It is also unclear if this is something you intend to do yourself, or if you're just curious on how oxidation is controlled in these experiments. If it is the latter, then shouldn't these papers that described the process tell you how they were done?

The problem here is that different techniques, and different purposes, have different level of controls of the oxidation process, depending on how accurate they want this. I do mine simply with a leak valve, a vacuum gauge, and an RGA to monitor the partial pressure of oxygen inside a UHV chamber, and then pump it back down after a sufficient length of time of exposure. I don't care that much about the accurate thickness of the oxide layer, only how reproducible I can make it.

So unless you have a specific purpose, or a specific paper and study that you wish to ask about, this remains a rather vague question to answer.

Zz.

 

[jarodparker198]

Read my first response. That was why I asked the INITIAL state that they are in, and why I said that your description was vague. You didn't tell me this important part of the scenario, i.e. surface cleaning. It is also unclear if this is something you intend to do yourself, or if you're just curious on how oxidation is controlled in these experiments. If it is the latter, then shouldn't these papers that described the process tell you how they were done?

The problem here is that different techniques, and different purposes, have different level of controls of the oxidation process, depending on how accurate they want this. I do mine simply with a leak valve, a vacuum gauge, and an RGA to monitor the partial pressure of oxygen inside a UHV chamber, and then pump it back down after a sufficient length of time of exposure. I don't care that much about the accurate thickness of the oxide layer, only how reproducible I can make it.

So unless you have a specific purpose, or a specific paper and study that you wish to ask about, this remains a rather vague question to answer.

Zz.

Hello,

I have in mind two papers:

- The first paper concerns the InSb material (J. Appl. Phys. 64, 2813 (1988); doi: 10.1063/1.341589)

- The second the InP and AsGa materials (Journal of Vacuum Science & Technology B 11, 2033 (1993); doi: 10.1116/1.586539)

In these two papers, they used UV light in different configurations (in a vacuum tool or at ambiant air) in order to oxidize the surface with a good control.

It seems that natural oxidization by introduction of O2 is not enough.

What do you think about these papers ?