1. Laboratory: A Typical Wet Etching Process

2. - Prepare chemicals.

3. - Mix chemicals in the proper ratios.

4. - Heat chemical mixture.

5. - Etch wafer.

6. - Remove wafer from the chemical etch solution.

7. - Rinse wafer.

8. A Typical Dry Etching
Process

9. - Prepare chamber.

10. - Load wafers.

11. -Plasma etch.

12. - Remove wafers.

13. A Typical Diffusion Process

14. - Prepare the source wafers (e. g
- Prepare the source wafers (e.g., ceramic wafers of LnP5O14 , which is a mixture of Ln2O3 and P2O5, as a source of P2O5 for P-doping).

15. - Verify that the diffusion furnace temperature is set (~ 850 °C for P ).

16. - Using teflon or teflon-tipped tweezers, carefully load the wafers into the quartz boat.

17. - The wafers should be inserted such that the device side of each is facing an P2O5 source wafer. There are two wafer slots between sources, allowing for a device wafer facing both sides.

18. - Return quartz boat, which now contains the wafers and sources, to the phosphorus furnace using the quartz boat loader.

19. - The phosphorus furnace needs to be heated to the temperature (~850 °C for P-doping) at which the diffusion will be performed.

20. - Begin nitrogen flow through the tube by setting the gas flow rate to a reasonable value (~3000 sccm).

21. - At the end of the process remove the boat from the furnace and allow the wafers to continue to cool before removing them from the wafer carrier.