rf in science and industry jonathan allen, ph.d. rf electronics consulting philadelphia conet
DESCRIPTION
RF in Science and Industry Jonathan Allen, Ph.D. RF Electronics Consulting Philadelphia CONET. What is RF?. Maxwell. James Clerk Maxwell 1831-79. RF Vs. Pwr. or LF. LF: S ystem dimensionsTRANSCRIPT
![Page 1: RF in Science and Industry Jonathan Allen, Ph.D. RF Electronics Consulting Philadelphia CONET](https://reader036.vdocuments.us/reader036/viewer/2022070419/56815a82550346895dc7ed39/html5/thumbnails/1.jpg)
1
RF in Science and IndustryJonathan Allen, Ph.D.
RF Electronics Consulting
Philadelphia CONET
![Page 2: RF in Science and Industry Jonathan Allen, Ph.D. RF Electronics Consulting Philadelphia CONET](https://reader036.vdocuments.us/reader036/viewer/2022070419/56815a82550346895dc7ed39/html5/thumbnails/2.jpg)
2
What is RF?
![Page 3: RF in Science and Industry Jonathan Allen, Ph.D. RF Electronics Consulting Philadelphia CONET](https://reader036.vdocuments.us/reader036/viewer/2022070419/56815a82550346895dc7ed39/html5/thumbnails/3.jpg)
3
Maxwell
![Page 4: RF in Science and Industry Jonathan Allen, Ph.D. RF Electronics Consulting Philadelphia CONET](https://reader036.vdocuments.us/reader036/viewer/2022070419/56815a82550346895dc7ed39/html5/thumbnails/4.jpg)
4
James Clerk Maxwell 1831-79
![Page 5: RF in Science and Industry Jonathan Allen, Ph.D. RF Electronics Consulting Philadelphia CONET](https://reader036.vdocuments.us/reader036/viewer/2022070419/56815a82550346895dc7ed39/html5/thumbnails/5.jpg)
5
RF Vs. Pwr. or LF
• LF: System dimensions << so propagation times are insignificant within system.
• RF: Phase diff. due to propagation times.
• RF: Skin effect = (2/ o)1/2 [mks]
• In RF plasmas, ion and electron migration per 1/2 cycle generally << sys. Dimensions.
• Small L and C values much more important
![Page 6: RF in Science and Industry Jonathan Allen, Ph.D. RF Electronics Consulting Philadelphia CONET](https://reader036.vdocuments.us/reader036/viewer/2022070419/56815a82550346895dc7ed39/html5/thumbnails/6.jpg)
6
LF Capacitors & Inductors
![Page 7: RF in Science and Industry Jonathan Allen, Ph.D. RF Electronics Consulting Philadelphia CONET](https://reader036.vdocuments.us/reader036/viewer/2022070419/56815a82550346895dc7ed39/html5/thumbnails/7.jpg)
7
RF Capacitors & Inductors
![Page 8: RF in Science and Industry Jonathan Allen, Ph.D. RF Electronics Consulting Philadelphia CONET](https://reader036.vdocuments.us/reader036/viewer/2022070419/56815a82550346895dc7ed39/html5/thumbnails/8.jpg)
8
ISM Bands (U.S.)
Center Freq. Bandwidth Availability
6.780 MHz 30 kHz Local acceptance*13.560 MHz 14 kHz Worldwide*27.120 MHz 326 kHz Worldwide*40.680 MHz 40 kHz Worldwide915.00 MHz 26 MHz Reg. 2 (Americas)2.45 Ghz 100 MHz Worldwide
![Page 9: RF in Science and Industry Jonathan Allen, Ph.D. RF Electronics Consulting Philadelphia CONET](https://reader036.vdocuments.us/reader036/viewer/2022070419/56815a82550346895dc7ed39/html5/thumbnails/9.jpg)
9
Examples of ISM RF• Heating of lossy materials
– Plastic welding (PVC)
– Cooking
– Drying
– Glue curing
– Medical (diathermy, ablation, cautery)
• Materials testing
• NMR/MRI
• Plasma processes– Sputtering & deposition
– Etching
– Spectroscopy
![Page 10: RF in Science and Industry Jonathan Allen, Ph.D. RF Electronics Consulting Philadelphia CONET](https://reader036.vdocuments.us/reader036/viewer/2022070419/56815a82550346895dc7ed39/html5/thumbnails/10.jpg)
10
RF HeatingPolar molecules flip orientation as e-field reverses. Some of the energy is dissipated as heat (dielectric loss).
![Page 11: RF in Science and Industry Jonathan Allen, Ph.D. RF Electronics Consulting Philadelphia CONET](https://reader036.vdocuments.us/reader036/viewer/2022070419/56815a82550346895dc7ed39/html5/thumbnails/11.jpg)
11
RF Gluing (also plastic welding)
![Page 12: RF in Science and Industry Jonathan Allen, Ph.D. RF Electronics Consulting Philadelphia CONET](https://reader036.vdocuments.us/reader036/viewer/2022070419/56815a82550346895dc7ed39/html5/thumbnails/12.jpg)
12
![Page 13: RF in Science and Industry Jonathan Allen, Ph.D. RF Electronics Consulting Philadelphia CONET](https://reader036.vdocuments.us/reader036/viewer/2022070419/56815a82550346895dc7ed39/html5/thumbnails/13.jpg)
13
![Page 14: RF in Science and Industry Jonathan Allen, Ph.D. RF Electronics Consulting Philadelphia CONET](https://reader036.vdocuments.us/reader036/viewer/2022070419/56815a82550346895dc7ed39/html5/thumbnails/14.jpg)
14
RF Drying
• Use for wood, foods, ceramic greenware
• Fast
• Selective--Heats only wet zones, uncured resins.
• Uniform in depth.
• Controllable – Reduce RF power as product approaches goal
• Often uses 27 or 40 MHz
![Page 15: RF in Science and Industry Jonathan Allen, Ph.D. RF Electronics Consulting Philadelphia CONET](https://reader036.vdocuments.us/reader036/viewer/2022070419/56815a82550346895dc7ed39/html5/thumbnails/15.jpg)
15
RF Drying Wood
SAGARF-VacuumTimber dryingsystem
![Page 16: RF in Science and Industry Jonathan Allen, Ph.D. RF Electronics Consulting Philadelphia CONET](https://reader036.vdocuments.us/reader036/viewer/2022070419/56815a82550346895dc7ed39/html5/thumbnails/16.jpg)
16
Drying Potato Chips
![Page 17: RF in Science and Industry Jonathan Allen, Ph.D. RF Electronics Consulting Philadelphia CONET](https://reader036.vdocuments.us/reader036/viewer/2022070419/56815a82550346895dc7ed39/html5/thumbnails/17.jpg)
17
RF Induction Heating• Usually uses LF ~100 KHz for metals
• Localized heating possible Zone refining
• No combustion products or oxygen (can heat in vacuum)
![Page 18: RF in Science and Industry Jonathan Allen, Ph.D. RF Electronics Consulting Philadelphia CONET](https://reader036.vdocuments.us/reader036/viewer/2022070419/56815a82550346895dc7ed39/html5/thumbnails/18.jpg)
18
Induction Heating Metal Rod
![Page 19: RF in Science and Industry Jonathan Allen, Ph.D. RF Electronics Consulting Philadelphia CONET](https://reader036.vdocuments.us/reader036/viewer/2022070419/56815a82550346895dc7ed39/html5/thumbnails/19.jpg)
19
Lab Measurement
The same properties of polar molecules that enable RF heating also measure moisture content of wood, flour, etc. with an RF capacitance bridge.
RF induction coils measure the thickness of metallic films and foils based on skin-depth.
![Page 20: RF in Science and Industry Jonathan Allen, Ph.D. RF Electronics Consulting Philadelphia CONET](https://reader036.vdocuments.us/reader036/viewer/2022070419/56815a82550346895dc7ed39/html5/thumbnails/20.jpg)
20
Plasmas Generate:
• Free electrons
• Positive ions
• Radicals
• Energetic particles
• Spallation of target (sputtering)
• Chemical reactions
• Excited atoms and molecules
• Light (glow discharge)
![Page 21: RF in Science and Industry Jonathan Allen, Ph.D. RF Electronics Consulting Philadelphia CONET](https://reader036.vdocuments.us/reader036/viewer/2022070419/56815a82550346895dc7ed39/html5/thumbnails/21.jpg)
21
Paschen Curves--Breakdown vs. PressureMFP (cm) = 5x10-3/p (torr)
![Page 22: RF in Science and Industry Jonathan Allen, Ph.D. RF Electronics Consulting Philadelphia CONET](https://reader036.vdocuments.us/reader036/viewer/2022070419/56815a82550346895dc7ed39/html5/thumbnails/22.jpg)
22
Plasma Sputtering
Energetic ions impact target and dislodge atoms ormolecules. These migrate to the substrate where they deposit to form a thin film.
Sputtering may be reactive, such as an aluminum target whose sputtered atoms reacting with oxygenin the process gas to form an Al2O3 film.
![Page 23: RF in Science and Industry Jonathan Allen, Ph.D. RF Electronics Consulting Philadelphia CONET](https://reader036.vdocuments.us/reader036/viewer/2022070419/56815a82550346895dc7ed39/html5/thumbnails/23.jpg)
23
Plasma Sputtering
![Page 24: RF in Science and Industry Jonathan Allen, Ph.D. RF Electronics Consulting Philadelphia CONET](https://reader036.vdocuments.us/reader036/viewer/2022070419/56815a82550346895dc7ed39/html5/thumbnails/24.jpg)
24
Plasma Etching
Plasma produces chemically active radicals which react with unmasked areas of wafer.This etches away material.
e.g. Fluorine radicals and ions etch silicon:
C F4 + e- C F3 + F + e-
Si + 4F Si F4
![Page 25: RF in Science and Industry Jonathan Allen, Ph.D. RF Electronics Consulting Philadelphia CONET](https://reader036.vdocuments.us/reader036/viewer/2022070419/56815a82550346895dc7ed39/html5/thumbnails/25.jpg)
25
Plasma Etching with Mask
Plasma
Mask
RF
DC field superimposed on RF helps accelerate F- ions
![Page 26: RF in Science and Industry Jonathan Allen, Ph.D. RF Electronics Consulting Philadelphia CONET](https://reader036.vdocuments.us/reader036/viewer/2022070419/56815a82550346895dc7ed39/html5/thumbnails/26.jpg)
26
Amorphous Si Plasma Deposition
SiH4 Si + 2 H2
![Page 27: RF in Science and Industry Jonathan Allen, Ph.D. RF Electronics Consulting Philadelphia CONET](https://reader036.vdocuments.us/reader036/viewer/2022070419/56815a82550346895dc7ed39/html5/thumbnails/27.jpg)
27
ICP Spectroscopy
![Page 28: RF in Science and Industry Jonathan Allen, Ph.D. RF Electronics Consulting Philadelphia CONET](https://reader036.vdocuments.us/reader036/viewer/2022070419/56815a82550346895dc7ed39/html5/thumbnails/28.jpg)
28
How to Generate RF
• Spark generator (obsolete, dirty)
• Power oscillator (efficient, cheap, but frequency not well defined)
• Oscillator (usu. xtal), driving Power amplifier (present industry standard)– Vacuum tubes– Bipolar transistors– Power FETs
![Page 29: RF in Science and Industry Jonathan Allen, Ph.D. RF Electronics Consulting Philadelphia CONET](https://reader036.vdocuments.us/reader036/viewer/2022070419/56815a82550346895dc7ed39/html5/thumbnails/29.jpg)
29
Power Oscillator
![Page 30: RF in Science and Industry Jonathan Allen, Ph.D. RF Electronics Consulting Philadelphia CONET](https://reader036.vdocuments.us/reader036/viewer/2022070419/56815a82550346895dc7ed39/html5/thumbnails/30.jpg)
30
Oscillator-Amplifier System
![Page 31: RF in Science and Industry Jonathan Allen, Ph.D. RF Electronics Consulting Philadelphia CONET](https://reader036.vdocuments.us/reader036/viewer/2022070419/56815a82550346895dc7ed39/html5/thumbnails/31.jpg)
31
Power Tubes 4-400C, 5CX1500A
![Page 32: RF in Science and Industry Jonathan Allen, Ph.D. RF Electronics Consulting Philadelphia CONET](https://reader036.vdocuments.us/reader036/viewer/2022070419/56815a82550346895dc7ed39/html5/thumbnails/32.jpg)
32
RF Power Transistor
![Page 33: RF in Science and Industry Jonathan Allen, Ph.D. RF Electronics Consulting Philadelphia CONET](https://reader036.vdocuments.us/reader036/viewer/2022070419/56815a82550346895dc7ed39/html5/thumbnails/33.jpg)
33
Impedance Matching
RF generators conventionally have 50 (resistive) output impedance.
Loads can have any complex (and varying) impedance. Matching networks allow the generator always to see a 50 resistive load and therefore operate efficiently.
![Page 34: RF in Science and Industry Jonathan Allen, Ph.D. RF Electronics Consulting Philadelphia CONET](https://reader036.vdocuments.us/reader036/viewer/2022070419/56815a82550346895dc7ed39/html5/thumbnails/34.jpg)
34
L Network
![Page 35: RF in Science and Industry Jonathan Allen, Ph.D. RF Electronics Consulting Philadelphia CONET](https://reader036.vdocuments.us/reader036/viewer/2022070419/56815a82550346895dc7ed39/html5/thumbnails/35.jpg)
35
Pi Network
![Page 36: RF in Science and Industry Jonathan Allen, Ph.D. RF Electronics Consulting Philadelphia CONET](https://reader036.vdocuments.us/reader036/viewer/2022070419/56815a82550346895dc7ed39/html5/thumbnails/36.jpg)
36
Univ. Matching Network, Can set as L or Pi
![Page 37: RF in Science and Industry Jonathan Allen, Ph.D. RF Electronics Consulting Philadelphia CONET](https://reader036.vdocuments.us/reader036/viewer/2022070419/56815a82550346895dc7ed39/html5/thumbnails/37.jpg)
37
Allen Matching Network
![Page 38: RF in Science and Industry Jonathan Allen, Ph.D. RF Electronics Consulting Philadelphia CONET](https://reader036.vdocuments.us/reader036/viewer/2022070419/56815a82550346895dc7ed39/html5/thumbnails/38.jpg)
38
Allen MN Physical Construction
![Page 39: RF in Science and Industry Jonathan Allen, Ph.D. RF Electronics Consulting Philadelphia CONET](https://reader036.vdocuments.us/reader036/viewer/2022070419/56815a82550346895dc7ed39/html5/thumbnails/39.jpg)
39
RF Instrumentation
• Current measurement
• Voltage measurement– Broadband– Frequency selective
• Directional power
• Circuit analysis
![Page 40: RF in Science and Industry Jonathan Allen, Ph.D. RF Electronics Consulting Philadelphia CONET](https://reader036.vdocuments.us/reader036/viewer/2022070419/56815a82550346895dc7ed39/html5/thumbnails/40.jpg)
40
RF Ammeter
![Page 41: RF in Science and Industry Jonathan Allen, Ph.D. RF Electronics Consulting Philadelphia CONET](https://reader036.vdocuments.us/reader036/viewer/2022070419/56815a82550346895dc7ed39/html5/thumbnails/41.jpg)
41
RF Ammeter (Square-law scale)
![Page 42: RF in Science and Industry Jonathan Allen, Ph.D. RF Electronics Consulting Philadelphia CONET](https://reader036.vdocuments.us/reader036/viewer/2022070419/56815a82550346895dc7ed39/html5/thumbnails/42.jpg)
42
Induction Ammeter
![Page 43: RF in Science and Industry Jonathan Allen, Ph.D. RF Electronics Consulting Philadelphia CONET](https://reader036.vdocuments.us/reader036/viewer/2022070419/56815a82550346895dc7ed39/html5/thumbnails/43.jpg)
43
VTVM with HF Probe (hp 410C)
![Page 44: RF in Science and Industry Jonathan Allen, Ph.D. RF Electronics Consulting Philadelphia CONET](https://reader036.vdocuments.us/reader036/viewer/2022070419/56815a82550346895dc7ed39/html5/thumbnails/44.jpg)
44
Calibrated Receiver (EMC-25)
![Page 45: RF in Science and Industry Jonathan Allen, Ph.D. RF Electronics Consulting Philadelphia CONET](https://reader036.vdocuments.us/reader036/viewer/2022070419/56815a82550346895dc7ed39/html5/thumbnails/45.jpg)
45
Single Frequency Detector
![Page 46: RF in Science and Industry Jonathan Allen, Ph.D. RF Electronics Consulting Philadelphia CONET](https://reader036.vdocuments.us/reader036/viewer/2022070419/56815a82550346895dc7ed39/html5/thumbnails/46.jpg)
46
Directional Wattmeter (Bird 43)
![Page 47: RF in Science and Industry Jonathan Allen, Ph.D. RF Electronics Consulting Philadelphia CONET](https://reader036.vdocuments.us/reader036/viewer/2022070419/56815a82550346895dc7ed39/html5/thumbnails/47.jpg)
47
RF Impedance Meter (hp 4815A)
![Page 48: RF in Science and Industry Jonathan Allen, Ph.D. RF Electronics Consulting Philadelphia CONET](https://reader036.vdocuments.us/reader036/viewer/2022070419/56815a82550346895dc7ed39/html5/thumbnails/48.jpg)
48
Grid Dip Meter (Measurements 59)
![Page 49: RF in Science and Industry Jonathan Allen, Ph.D. RF Electronics Consulting Philadelphia CONET](https://reader036.vdocuments.us/reader036/viewer/2022070419/56815a82550346895dc7ed39/html5/thumbnails/49.jpg)
49
Important Uses of RF
• Food
• Construction
• Metallurgy
• Semiconductors (Discrete, IC, Photovoltaic)
• Optics
• Health and Medicine
• Laboratory science