Table of Contents
Understanding thee built- in potential in semicontentor junctions is essential for designing and analyzing electronicic devices. This article explores praktical methods to determinate this important parameter prequateley.
Metodika 1: Kapacita Voltage (C-V) Měření
Te C-V measurement involves analyzing the depletion region of a dioda. By appliying a reverse bias and measuring the capacitance, thee built- in potential can be calculated using the relation:
CLANE1; CLANE1; CLANE1; CLANE3; V _ bi = (kT / q) * ln (N _ A * N _ D / n _ i ^ 2) + V _ R CLANE1; CLANE1; CLANE1; CLANE3; CLANE3c;
Where V _ bi is the built-in potential, N _ A and N _ D are doping concentraratis, n _ i is the intrinsic carrier concentration, V _ R is thae applied reverse bias, and Theor symbols have e their usual concentration.
Method 2: Open- Circuit Voltage Method
This method measures thee open- circuit voltage (V _ OC) of a diode under lightination. Te V _ OC is related to thee built- in potential by te equation:
CLAS1; CLAS1; CLAS3; CLAS3; V _ OC CLAS3V _ bi - (kT / q) * ln (I _ L / I _ 0) CLAS1; CLAS1; CLAS3; CLAS3FLAS3; CLAS3d;
Here, I _ L is the fotokurrent, and I _ 0 is the saturation curt. By measuring V _ OC and knowing the currentcenes, V _ bi can bee estimated.
Metodika 3: Elektroluminiscence a fotolumininescence
Optical methods mimpeve analyzing thee emission spectra of the junction. Thee peak emission vlhoength relates to thee energiy gap, which can bee used to determinae thee built- in potential indirectly.
These methods are useful for materials where electrical measurements are conditing.
Summary
- Kapacita - Voltage measurement
- Open- Circuit Voltage metodid
- Optical emission analysis