Fabrication process of pn junction is explained briefly

1. ANIL PRASAD DADI/ECE/ANITS
ANIL NEERUKONDA INSTITUTE OF TECHNOLOGY & SCIENCES(A)
Department of Electronics and Communication Engineering
ECE 125 Basic Electronics Engineering
 Academic year : 2022-23
 Class & Section : 1/4 ECE-A
 Name of the Faculty : Mr.D.Anil Prasad

2. UNIT-I(Semiconductor Diodes)
• Fermi level in Intrinsic & Extrinsic semiconductors. Mass-Action law.
Mobility and conductivity, Hall effect, Generation and recombination of
charges, Drift and diffusion current, Band structure of open-circuit p-n
junction, V-I characteristics, transition and diffusion capacitance, reverse
recovery time, Avalanche and zener breakdown, zener diodes, Light
Emitting Diodes.
ANIL PRASAD DADI/ECE/ANITS

3. PN junction fabrication
• Step1: start with n+ substrate with n epitaxial layer grown on top
ANIL PRASAD DADI/ECE/ANITS

4. PN junction fabrication
• Step2: Deposit Sio2
ANIL PRASAD DADI/ECE/ANITS

5. PN junction fabrication
• Step3: Apply Photo resist
ANIL PRASAD DADI/ECE/ANITS

6. PN junction fabrication
• Step4: Place mask
ANIL PRASAD DADI/ECE/ANITS

7. PN junction fabrication
• Step5: Expose to UV light
ANIL PRASAD DADI/ECE/ANITS

8. PN junction fabrication
• Step6: Remove mask
ANIL PRASAD DADI/ECE/ANITS

9. PN junction fabrication
• Step7: Develop photo resist
ANIL PRASAD DADI/ECE/ANITS

10. PN junction fabrication
• Step8: Etch oxide (in HF)
ANIL PRASAD DADI/ECE/ANITS

11. PN junction fabrication
• Step9: Remove photo resist
ANIL PRASAD DADI/ECE/ANITS

12. PN junction fabrication
• Step10: Perform diffusion of Boron
ANIL PRASAD DADI/ECE/ANITS

13. PN junction fabrication
• Step11: Add metal contacts
ANIL PRASAD DADI/ECE/ANITS

14. PN junction fabrication
• Step12: PN junction formation
ANIL PRASAD DADI/ECE/ANITS

15. Thank you
for listening