For Hall measurements if all the electrical connections are correct then positive and negative sign the Hall voltage is due to carries type of the sample of course the case for semiconductors

I agree with the answer of Omar M S.

in Hall effect positive and negative sign the Hall voltage is due to carrier concentration of the sample.

Hello everyone,

Of course, i agree with Omar and Vivek, and I advise Cyril to consult a book of fundamental university physics (ALONSO & FINN, SERWAY et al, ...) . Nevertheless, I will recall some important results of the Hall effect : Depending on the sign of the voltage (with an accurate experimental setup), we can determine the sign of the charge carriers. If the carriers of charges are electrons, we will speak of negative Hall effect. However, if the charge carriers are of positive sign, it appears a positive Hall effect. In a semiconductor, the conduction is ensured by two types of charge carriers: the electrons and the holes, respectively negative and positive charges..

Regards.

As the colleagues above hinted positive and negative Hall voltage depends on the conduction type of your film. In order to give specific answers on your questions you have to describe the doping of your film. I think the question needs to more details.

Best wishes

The answers given are correct if the question was on the meaning of the sign of the measured Hall voltage.This guy is asking about the sign of the bulk and sheet concentrations.I have seen cases in which the bulk and sheet concentrations are negative or positive.So the question is the physical meaning of the negative values of the bulk and sheet concentration ?

I have attached some measurement results with negative bulk(Nb) and sheet(Ns) concentrations.WHAT DO THESE RESULTS MEAN?

NOTE:All the connections and measurement procedure was properly done.These results are obtained using Ecopia HMS-3000