The Hall effect, discovered by Edwin Hall in 1879, describes the generation of a voltage across a conductor when a magnetic field is applied perpendicular to the flow of electric current. This phenomenon occurs due to the Lorentz force acting on charged particles, resulting in the development of Hall voltage. It is notably utilized in p-type semiconductors where the movement of positive charge carriers enables the measurement of magnetic fields through devices such as Hall sensors.

1. HALL EFFECT
DISCOVERY
 THE HALL EFFECT WAS DISCOVERED IN 1879 BY THE
U.S. PHYSICIST EDWIN HERBERT HALL.
 DISCOVERED 18 YEARS BEFORE THE ELECTRON.
 PUBLISHED UNDER THE NAME
“ON A NEW ACTION OF THE MAGNET ON ELECTRIC CURRENTS.”

2. WHAT IS HALL EFFECT?
• WHEN A MAGNETIC FIELD IS APPLIED PERPENDICULAR TO A CURRENT CARRYING
CONDUCTOR OR SEMICONDUCTOR, VOLTAGE IS DEVELOPED ACROSS THE SPECIMEN IN A
DIRECTION PERPENDICULAR TO BOTH THE CURRENT AND THE MAGNETIC FIELD.
• THIS PHENOMENON IS CALLED THE HALL EFFECT AND VOLTAGE SO DEVELOPED IS CALLED
THE HALL VOLTAGE.
• IT IS WELL ESTABLISHED THAT THE HALL-EFFECT RESULTS FROM THE INTERACTION OF CHARGED
PARTICLES, LIKE ELECTRONS, IN RESPONSE TO ELECTRIC AND MAGNETIC FIELDS.

3. THEORY
o WHEN A CURRENT CARRYING CONDUCTOR IS PLACED INTO A MAGNETIC
FIELD, A VOLTAGE WILL BE GENERATED PERPENDICULAR TO BOTH THE
CURRENT AND THE MAGNETIC FIELD.
o WHEN A PERPENDICULAR MAGNETIC FIELD IS PRESENT. A LORENTZ FORCE
IS EXERTED ON THE ELECTRON. DUE TO WHICH ELECTRON MOVES IN
PERPENDICULAR DIRECTION TO BOTH CURRENT AND MAGNETIC FIELD.
AND DEVELOP A POTENTIAL DIFFERENCE ACROSS THE CONDUCTOR OR
SEMICONDUCTOR.
o CREATES INTERNAL ELECTRIC POTENTIAL, KNOWN AS HALL VOLTAGE.

4. HALL EFFECT IN P-TYPE
SEMICONDUCTORS
 IN A P-TYPE SEMICONDUCTOR, POSITIVE CHARGE CARRIERS (HOLES) MOVE
WHEN A MAGNETIC FIELD IS APPLIED.
 THIS MOVEMENT CREATES A VOLTAGE, KNOWN AS THE HALL VOLTAGE,
ACROSS THE SEMICONDUCTOR.
 THE HALL EFFECT IN P-TYPE SEMICONDUCTORS IS USED IN DEVICES LIKE HALL
SENSORS TO MEASURE MAGNETIC FIELDS.