1. Dilbert

5. Next steps in the antenna fabrication process
Create a dielectric surface. The antenna must sit on a dielectric or insulating surface, not a semi-conducting surface.
Determine the best conductor for the antenna. The actual antenna will be made out of a conducting metal

6. High Temperature Furnace (used to grow SiO2 on the wafer)
Gas Control Cabinet
Robot loader
Quartz tube
Quartz wafer carrier
Temperatures can range from 900oC to 1200oC with uniformity of 2oC over a distance of 36 inches

7. Quartz wafer carrier is never removed from robot arm
Furnaces are color coded to prevent contamination. Furnace # 7 is marked as “RED” and is used only for silicon dioxide formation on virgin clean wafers
Quartz wafer carrier is never removed from robot arm

8. Oxygen tanks in service bay
Check oxygen tanks in service bay for proper pressure

9. Hydrogen tank in service bay
Check hydrogen tank for proper pressure

10. Furnace gas cabinet-controls the atmosphere inside each furnace tube

11. Gas panel for furnace #6

12. Verify all gauges read about 20 psi

13. Power lamp does not work
Manual mode only
Nitrogen gas is ALWAYS “ON”
T/C POS and Auto Ign “ON”

14. Loading wafers
Wafers are loaded into quartz oxidation boats at the furnace. Quartz boats are NEVER moved or touched

15. Robot Loader to insert and remove wafers from the furnace
Speed is NOT adjusted
Load/Unload switch

16. Wafers entering the furnace

17. Typical Oxidation Process
Load in N2
5 minutes in N2 and O2 (dry oxidation)
30-60 minutes N2+O2+H2 (wet oxidation or steam oxidation)
5 minutes in N2 +O2
Unload in N2

18. Wafers being unloaded
Wafers are unloaded at the robot arm. Again, the quartz boats are never moved or touched

19. Once the SiO2 is formed, the wafers will have a different color, wafer color is based on the thickness of the SiO2

20. Besides being a dielectric (insulating) layer, the SiO2 has another very important role to play in microelectronics, that of a barrier to the doping of silicon

21. n-type silicon wafer shown in cross-section

22. At high temperature with an oxygen atmosphere the silicon dioxide forms on all silicon surfaces

23. Using a photolithography process, small holes are created in the silicon dioxide exposing bare silicon

24. Again, at high temperature, a p-type dopant (boron) is introduced
Again, at high temperature, a p-type dopant (boron) is introduced. The boron can not penetrate the silicon dioxide but can penetrate the bare silicon and diffuses into the silicon forming a p-n junction

25. If a diode was the end product, the silicon dioxide is removed from the back side (if not already removed in previous steps) and metal contacts, usually aluminum are deposited on top and bottom creating a p-n diode. For more complex devices, the steps are repeated

26. Once the dielectric has been formed on the silicon wafer
It is time to decide on a conductor to create the antenna.
Conductor attributes will be evaluated
Your team will create a decision matrix using a simple EXCEL spreadsheet to determine the conductor for your project
The conductor chosen will be deposited on your wafers next week

27. Conductor Attributes

29. Sample Conductor Decision Matrix
Create a title for the spreadsheet
Decide on weights for each attribute
Decide on conductor rank for each attribute based on attributes chart
Multiply weight times rank for each conductor
Add the columns
The conductor of choice is the one with the largest total

30. Homework
Create a conductor decision matrix using the conductor attributes chart.
Homework #9 on the web site
Both the conductor attributes chart and a sample decision matrix are available on the web site
This is a team assignment, only one per team
Preview before submission
Make sure entire spreadsheet prints on one page
Include “Title” with team name
Use gridlines
Highlight the conductor of choice

31. Test on Monday Multiple choice plus some calculation problems
Test will cover
Four research areas – Cellular, “Bluetooth” & Wi-Fi, RFID, GPS
Clean room safety and protocols
Finding wavelength from frequency and finding frequency from wavelength
Study guide will be sent via