This document discusses adiabatic deposition and surface modification techniques using pulsed energy beams. 1) Adiabatic processes use pulse durations shorter than the thermalization time so that energy is deposited into the material faster than it can conduct away as heat. This allows modifying properties without significantly changing temperature. 2) An example is shown where an electron beam causes localized heating allowing re-crystallization of semiconductor and superconductor materials. 3) Applications include depositing thin films and coatings using ion or electron beams as well as mixing deposited layers with the substrate through ion bombardment.

1. Adiabatic deposition of
films/coatings and adiabatic
surface modification of
materials
Dr. Sergey Korenev
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2. Content
1. Introduction.
2. Main principles of adiabatic
technologies.
3. Examples of applications.
4. Conclusion.
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3. Goal and motivation
• Information about new method of
deposition of films and coatings and
surface modification of materials by pulsed
beams.
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4. Main concept
ELECTRO-KINETIC TRANSFORMER
OF ENERGY
Energy storage
Capacitor
E = CU2/2
Potential
energy
Charge particle
transformer
E = N*mv2/2
Kinetic
energy
Object condensed
matter
Dissipation
of energy
Small size of particles, high speed,
penetration and depth of penetration
depends on kinetic energy
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5. Definition of adiabatic processes for
materials
• The main parameter of this process ( technology) is
time:
tbeam  ttherm 
2h   C
2

where: tbeam is pulse duration of energy source, tthermal is
time of dissipation of energy – heating, h is depth of
penetration for energy source in irradiated sample;
,C, are respectively density, heat capacity and heat
conductivity of target.
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6. Electrons
D
E U  I tp  N
[J ]


 [Gray]
m   Lopt  a  b [kg]
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7. Example of adiabatic re-crystallization
of materials by e-beam
E-beam
Penetration of
beam: X =F ( W)
Beam
current
time
Sample
Temperature Absorbed e-beam
dose
gradient
Temperature
1
2
3
time
Distance
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8. Re-crystallization
Semiconductor
HTSC
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9. Ion beams
• The difference between electrons consists
in the different mass and different depth of
penetration of ions to matter.
• Types of ions: all periodical element table.
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10. Pulsed ion/electron diode method for
deposition and modification of films
Substrate
Ion/Electron
Diode
Cathode/
Anode
Holder
Anode/
Cathode
Marx pulsed
high voltage
generator
Vacuum
system
Control and
monitoring
system
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11. Voltage
tvoltage<tion
Ion current
Voltage
time
Main processes:
time
tvoltage>tion
Ion current
time
Full current of
diode
time
time
•Cleaning of surface of substrate by
first pulse ion beam as a result of
ions bombardment.
•Ion mixing of deposited layers with
substrate until the kinetic energy
ions will be enough for penetration.
Typically it is few tens –hundred
layers and depends on type of ion
and material of film.
*Deposition of films and growing of
film structure on the substrate
without heating.
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12. Mixing of film and substrate
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13. Economical question
1. Cost of equipment: $M 0.05-1.0
2. Efficiency: 75-80%.
3. Time of treatment: from single pulse to 510 minutes ( in compared with diffusion
process few hours).
Disadvantages:
1. Qualified operation.
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14. Applications of adiabatic
technologies
• Metals and alloys.
• Semiconductors.
• Polymers and dielectrics.
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