If it is possible to classify different compound semiconductors as n type and p type, please help whether the ZnS and CdS are n type or p type.
Dear Antony
Hot point probe technique was used to determine the conductivity type of the films. The hot point probe test is a common technique for rapidly determining the type of semiconductor. A hot and a cold probe are connected with a voltmeter as shown in Fig(see file)., hot probe creates excess majority carriers that diffuse away leaving net charge buildup
are you talk a specific sample you have prepared or as a general concept ?
You can determine the semiconductors whether they are n-type or p-type by Mott-Schottky analysis. This is an easy method for the determination of n-or p-type behavior...
In general, the majority carrier types in semiconductors can be determined by Hall effect or hot probe analysis. However, if you are asking particularly about II-VI semiconductors like ZnS, CdS, CdTe, ZnTe etc, then it can be noted that most of the II-VI semiconductors have strong preference to any one type of conductivity due to the self compensation effect. For example, CdS, ZnS have strong preference to n-type. It is very difficult to dope them p-type. On the other hand, ZnTe has strong preference to p-type. If I am not wrong, CdTe is the only II-VI compound which can be doped easily with n-type and p-type dopants.
Ideally, such compound semiconductors are intrinsic but as hinted at above, they have a propensity to be either p-type or n-type due to characterisic defects associated with their formation and the environment. For instance, ZnO tends to be n-type as it is prone to contain oxygen vacancies which tend to result in a very high density of free electrons. The engineering challenge is to suppress such effects so that the doping level can be controlled.
Dear Dr Anil Kumar Reddy Police;
Could you please, give us more details about how to identify SC type from cyclic voltammetry ?
zetapotential study can also be very useful to identify the type of major charge carriers are either electron are holes
Gowrish Rao thank you very much for your answer. What is the reason that CdS have strong preference to n-type. It would be very helpful if you can suggest me any reference.
Subham Paramanik The doping limitations in II VI semiconductors such as CdS ZnS etc are well documented in the following papers.
1. Doping limits in II–VI compounds — Challenges, problems and solutions, UV Desnica, Progress in Crystal Growth and Characterization of Materials Volume 36, Issue 4, 1998, Pages 291-357
2. The Problem of Doping in II-VI Semiconductors, D J Chadi, Annual Review of Materials Science Vol. 24:45-62 (Volume publication date August 1994)
3. Amphoteric nature of vacancies in zinc blende semiconductors D J Chadi, Materials Science in Semiconductor Processing Volume 6, Issues 5–6, October–December 2003, Pages 281-284
electrons are major charge carrier in n-type materials while holes are in p-type so first, do the photoelectrochemical study TP, EIS and scavenger study to identify the nature of the material
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