Unit II. Theory of pvd Coatings

Before you start: Think it over. Agree-Disagree

“Nothing great was ever achieved without enthusiasm.”

Emerson, Ralph Waldo

Note: Ralph Waldo, 1803-1802, US essayist and poet

Reading, Vocabulary & Creative Practice

1. Words to be remembered.

auxiliary dielectric ionization produce

bias sputtering deliberate magnetron RF

bombardment development obsolete reason

combination emit patent supply

concurrent epitaxial growth possible variation

confine invention pressure voltage

cost investigate PVD trap

2. Translate the sentences. Define the predicates. Pay attention to the words in italics.

1. The radar beam is confined within a small angle.

2. Please confine your remarks to the subject under discussion.

3. Magnetron is a two-element vacuum tube in which the flow of electrons is under the influence of an external magnetic field, used to generate extremely short radio waves.

4. The chimney emitted a cloud of smoke.

5. Mobile phone is a wonderful invention.

6. The film was highly praised, but was not a commercial success.

7. PVD is abbreviation from physical vapor deposition.

8. Physicists speak about ion, neutron and electron bombardment.

9. Of several concurrent reactions, only one is the main reaction.

10. These gas containers will burst at high pressures.

11. If you don’t patent your invention someone steal your idea.

12. This equipment became obsolete.

13. Twenty miners were trapped underground.

14. Gas can be produced from coal.

15. The electricity supply has been threatened by recent strikes.

16. Voltage is the electrical energy that moves charge around a circuit.

17. The percentage ionization is equal to the degree of ionization x 100.

18. The patent runs out in two years time.

3. Read text A carefully. Pay attention to the words in bold type. Comment on the underlined grammar peculiarities.

A. Electricity & Magnetism

The development of vacuum technology, electricity and magnetism and gaseous chemistry plays an important part in vacuum technology history and its evolution. The history of PVD is also known to be closely associated with the development of vacuum technology, the discovery of electricity and magnetism and the understanding of gaseous chemistry. The property of producing or being affected by magnetic field is called magnetism. Magnetism is also the study of magnets and effects of magnetic fields.

An understanding of magnetic phenomena is essential for anyone working on the practical application of electromagnetic theory. Thus, in the late 1930s Penning (an American scientist) developed an “electron trap” to confine electrons near a surface using a combination of electric and magnetic fields. This combination of electric and magnetic fields increased the ionization of the plasma near the surface and was named a “Penning Discharge” after its inventor. Penning used his invention to sputter from the inside of a cylinder. This was an important development in the history of sputtering and a basic magnetron. Such a combination of electric and magnetic fields allowed sputtering to be performed at lower pressures and lower voltages, and at a higher deposition rates than were previously possible with DC sputtering without magnets. Variations of the Penning magnetron have subsequently been developed.

Comprehension Check – 1

4. Decide whether the following statements are true or false according to text A.

1. In 1930s Penning developed an “electron trap” to confine electrons near a surface.

2. The combination of electric and magnetic fields increased the ionization of the plasma.

3. This combination was named a “Penning Discharge” after the name of the inventor’s brother.

4. Penning used his invention to sputter from the outside of a bottle.

5. Such a combination of electric and magnetic fields allowed sputtering to be performed at lower pressures.

6. Variations of the Penning magnetron have never been changed.

5. Answer the following questions to text A.

1. What is magnetism?

2. For whom are magnetic phenomena essential?

3. What is the aim of “electron trap”?

4. What increased the ionization of the plasma near the surface?

5. What was the Penning’s invention?

6. What did the combination of electric and magnetic field allow?

7. Has magnetron or telephone subsequently been developed?

6. Read text B carefully paying attention to the words in bold type.

B. Sputtering

The use of radio frequency (RF) to sputter material was investigated in the 1960’s. That time scientists used RF sputtering to produce dielectric films from a dielectric target. Besides, they co-sputtered glass using RF and metals Al, Cu, Ni. But RF sputter deposition was not used extensively for commercial PVD for several reasons. The major reasons are: it is not economic to use large RF power supplies due to their high cost and the fact that you introduce high temperatures.

In 1962 Wehner patented the process of deliberate concurrent bombardment “before and during” sputter deposition using a “bias sputter deposition” arrangement and mercury ions to improve the epitaxial growth of silicon (кремниевый) films on germanium (германиевый) substrates. Later this process became known as bias sputtering. The term reactive sputtering was introduced in 1953. Reactive sputter deposition of tantalum nitride for thin film resistors was an early application. However it wasn’t until the mid-1970s that reactively sputter-deposited hard coatings on tools began to be developed and they became commercially available in the early 1980s.

The triode sputtering configuration uses auxiliary plasma generated near the sputtering cathode by a thermo-electron emitting electrode and a magnetically confined plasma. This configuration was used to increase the level of ionization in the plasma but became obsolete with the development of magnetron sputtering.

7. Decide whether the following statements are true or false according to text B.

1. The scientists co-sputtered glass using RF and metals.

2. RF sputter deposition was used extensively.

3. In 1962 Wehner patented the process of deliberate concurrent bombardment.

4. Wehner wanted to improve the epitaxial growth of silicon films on copper substrate.

5. The triode sputtering configuration uses auxiliary plasma.

6. The configuration was used to increase the level of ionization.

8. Answer the following questions to text B.

1. What was investigated in 1960’s?

2. What metals did scientists use in co-sputtering?

3. Why RF sputter deposition was not used extensively?

4. What process became known as bias sputtering?

5. What kind of plasma does the triode sputtering configuration use?

6. Is auxiliary plasma generated near cathode or anode?

7. What became obsolete with the development of magnetron sputtering?

8. What stands for RF?

9. What is the Russian for “Triode” sputtering?

10. Give the full names of the following metals Al, Cu, Ni.

Comprehension Check – 2

9. Make sure you know the meanings of these words. Use a dictionary. Match the words with their definitions. Some prompts are made for you.

Accelerate; activation; adhesion; amorphous; blanket; bombardment; ceramics; chamber (evacuated vessel); coating; crack; diffusion; etching; initial; inert; roughness; substrate (substratum); surface; treatment

1. making pure by passing air through = a...n

2. cause faster movement in = a...e

3. having no fixed form or shape = a...s

4. attack with (ions) = b...t

5. the molecular attraction between unlike bodies contacted = a...n

6. making articles by shaping pieces of clay and baking them until they are hard = c...s

7. a covering on or over a surface = c...g

8. which is at the beginning = i...l

9. very thin mark or opening caused by breaking = c…k

10. spread widely or thinly = d...n

11. not acting chemically when combined with other substances = i...t

12. cutting or corroding with an acid or the like = e...g

13. an enclosed space = c...r, e...l

14. any covering or layer = b...t

15. that which is spread or laid under something else = s...te

16. an outer part of an object = s...ce

17. an uneven surface, not smooth = r...s

18. putting something trough a chemical /industrial process in order to change it = t...t

10. Translate the following sentences from an article, which describes the present-day ionic treatment peculiarities. Make use of the words from the above exercise 8. Bear in mind that English is often more laconic than Russian.

1. Это статья об ионной обработке поверхности стеклянных изделий.

2. Завершающим этапом подготовки изделий под нанесение вакуумно-плазменных покрытий является ионная обработка, которая осуществляется в вакуумной камере.

3. Ионная обработка – это бомбардировка поверхности подложки ускоренными высокоэнергетическими ионами материала катода.

4. Ионная бомбардировка производится с целью очистки и термической активации поверхности.

5. Качество и эксплуатационные характеристики покрытий определяются на этапе подготовки поверхности.

6. Ученые уделяют основное внимание изменению характера шероховатости поверхности после ионной обработки, а также адгезии покрытия.

7. В настоящее время вакуумно-плазменные методы находят широкое применение для нанесения покрытий на изделия из аморфных материалов (стекло, керамика и др.)

8. На данном этапе ставится задача исследования влияния ионной обработки на изменение параметров шероховатости, знак и величину напряжений поверхностного слоя изделия из стекла.

11. Match the words with the synonyms.

1) confine 5) commercial a) technique e) produce

2) method 6) concurrent b) limit f) industrial

3) improve 7) several c) better g) some

4) generate 8) configuration d) parallel h) shape

12. Match the words with their antonyms.

1) external 5) inside a) smooth e) decrease

2) unique 6) possible b) open f) lower

3) rough 7) closed c) internal g) ordinary

4) higher 8) increase d) impossible h) outside

13. Translate & remember the following logical combinations of the branches and the throughput modes (виды производительности) used in the present-day Vacuum Technology Applications throughout the world and in Belarus.

1. Aluminum Production	a) Vacuum containment
2. Potting (ceramics)	b) Clay deaeration
3. Polygraphy	c) Pressing, paper containment
4. Carpet production	d) Vacuum drying
5. Tinned food production	g) Vacuum containment, preserving
6. Beer production	h) Water degassing, water filling
7. Soap production	I) Vacuum forming, packaging
8. Textile Industry	j) Vacuum dehydration, drying
9. Poultry processing	m) Removal of feathers, packaging
10.Water-purifying stations	n) Vacuum filtration
11. Tire production	o) Vacuum degassing
12. Leather working	p) Vacuum dehydration, drying

14. Match the Russian Equivalents with the English, describing the basic processes of production.

1) удержание 5) формообразование 9) упаковка

2) деаэрация 6) обезвоживание 10) наполнение

3) фильтрация 7) прижим 11) сушка

4) консервирование 8) дегазация 12) удаление перьев

а) filtration e) containment i) forming

b) drying f) deaeration j) dehydration

c) filling g) packaging k) feather removal

d) preserving h) degassing l) pressing

15. Translate, then set up a correspondence of the branches of production with the application processes. Apply to Exercise 13.

Производство: 1. алюминия, 2. керамики, 3. ковров, 4. консервов, 5. пива, 6. мыла,7. текстильных изделий, 8. шин, 9. водоочистные станции, 10. обработка кожи, 11. переработка птицы, 12. полиграфия

Применение: а) деаэрация b) обезвоживание c) удержание d) сушка f) прижим g) формообразование h) консервирование i) упаковка j) дегазация k) фильтрация l) наполнение m) удаление перьев

16. Grammar Tutorials: Prepositions Read texts A & B again. Fill in the correct prepositions.

1. Penning developed an “electron trap” to confine electrons … a surface.

2. Penning used his invention to sputter … the inside of a cylinder.

3. This was an important development … the history of sputtering.

4. Such a combination of electric and magnetic fields allowed sputtering to be performed … lower pressures.

5. Variations … the Penning magnetron have been developed.

6. The use of RF to sputter material was investigated … the 1960.

7. But RF sputter deposition was not used extensively … several reasons.

8. Later this process became known … bias sputtering.

Additional Activities: Miscellaneous

17. Match the parts of the sentences.

1) electricity and magnetism a) to conform electrons near

the surface

2) electron trap was developed b) play an important part

in vacuum history

3) magnetism is the study of c) have been developed

4) the term reactive sputtering d) magnetic fields effects

5) variations of the magnetron e) was introduced in 1953

18. Compare the equivalents of the text “Benefits of Vacuum Drying”.

1. Vacuum drying is ideal for the materials that would be damaged or changed if exposed to high temperatures. The vacuum removes moisture while preventing the oxidation or explosions.	1. Вакуумная сушка является идеальным средством для мате-риалов, которые могут быть повреждены или изменены при воздействии высоких температур. Вакуум удаляет влагу, не допуская окисления и взрывов.
2. Vacuum drying saves time. Unlike atmospheric drying, drying under reduced pressure lowers the boiling point and provides a greater temperature difference between the heating medium and product. This results in faster drying and more efficient heat recovery.	2. Вакуумная сушка экономит время. В отличие от атмосферной сушки сушка при пониженном давлении позволяет снизить температуру кипения и обеспечи-вает большую разницу температур теплоносителя и продуктов. Это приводит к ускорению высыхания и более эффективной рекуперации тепла.
3. Vacuum drying saves money. Drying at lower temperatures reduces energy consumption. The dryers’ closed- system (or structural loop) design eliminates expenses for additional air-pollution control.	3. Вакуумная сушка экономит деньги. Высушивание при более низких температурах сокращает потребление энергии. Замкнутая сушильная конструкция исклю-чает затраты на дополнительный контроль загрязнения воздуха.
4. Vacuum drying protects workers. Since drying occurs in a closed system, hazardous materials and fumes are not released into the air. The potential for explosions is reduced because of the lower temperatures and the lack of dust and air in the dryer.	4. Вакуумная сушка защищает рабочих. Поскольку сушка проис-ходит в замкнутой системе, опасные вещества и дым не выбрасываются в атмосферу. Вероятность взрывов снижается из-за более низких температур и отсутствия пыли в воздухе.

19. Scan the text “Surface Preparation” and define the main idea of the text orally.

Surface preparation is an essential step in all vacuum coating processing and is critical to the nucleation and interface formation steps of the coating process. These “prepared” surfaces, in turn, determine the adhesion of the coating, the surface coverage, and – in many cases – the structure and the properties of the resulting deposit. Surface preparation includes not only cleaning but in some cases modification of the chemical, morphological, or mechanical properties of the surface or the near-surface region. These changes can affect the nucleation of the depositing atoms on the surface and the growth of the coating. Cleaning comprises both that done external to the deposition chamber (external cleaning) and that done in the deposition chamber (in situ cleaning).

External cleaning for vacuum coating is generally similar to that used in other manufacturing processes of the type called “critical cleaning” or “precision cleaning”. Precision cleaning is sometimes defined as “cleaning a surface that already looks clean”. A few external cleaning techniques have been developed specifically for vacuum coating or were initially used for vacuum coating. These include ultraviolet-ozone (UV/03) oxidative cleaning and sputter (physical) cleaning.

An important aspect of cleaning is to avoid contamination of the surface with particulates. Particulates are a primary cause of pinholes in films deposited on smooth surface.

20. Make complete translation of the text from “Vacuum Technology & Coating” magazine in a written form. Some prompts are given for you.

Modern Servicing Industry Markets: Vacuum Processing.

The magazine's editorial objective is to cover all areas of vacuum processing in all industries. However – as indicated by the title – the primary editorial focus is on vacuum deposition, the depositing of metals onto non-metallic substances, also generically known as thin film deposition (напыление тонкопленочных покрытий). The largest single process utilized throughout all industries is physical vapor deposition – a combination of processes referred to as sputtering (напыление) and evaporation (выпаривание). Other vacuum processes such as ion implantation (ионная имплантация), etching (травление), plasma processing, (плазменная обработка) crystal growing (выращивание кристаллов), chemical vapor deposition (химическое осаждение из паровой или газовой среды) are also covered, as is lithography (литография) in a few specific markets.

21. Scan the biography. Put questions to the given answers.

Ludwig Eduard Boltzmann was born February 20, 1844, in Vienna and died on September 5, 1906, in Italy. He was an Austrian physicist whose greatest achievement was in the development of statistical mechanics, which explains and predicts how the properties of atoms such as mass, charge, and structure determine the visible properties of matter such as viscosity, thermal conductivity, and diffusion.

After receiving his doctorate from the University of Vienna in 1866, he held professorships in mathematics and physics. He contributed substantially to the foundation and development of statistical mechanics, a branch of theoretical physics.

The Boltzmann constant, k, is a fundamental constant of physics occurring in nearly every statistical formulation of both classical and quantum physics.

In the 1870s Boltzmann published a series of papers. He showed that the Second Law of Thermodynamics, which concerns energy exchange, could be explained by applying the laws of mechanics and the theory of probability to the motions of the atoms. Boltzmann worked out the general law for the distribution of energy. He also derived the theorem of energy known as the Maxwell-Boltzmann law. This law states that the average amount of energy used for each different direction of motion of an atom is the same.

Boltzmann was also one of the first Europeans to recognize the importance of the electromagnetic theory. His work on statistical mechanics was strongly attacked by many who did not believe in the atomic theory and wanted to base all of physical science on energy considerations only. His conclusions were finally supported by the series of discoveries in atomic physics.

1) No, Boltzmann was a physicist.

2) He held professorships both in physics and mathematics.

3) It is a fundamental constant of physics.

4) A series of papers.

5) Yes, he recognized the importance of the electromagnetic theory.

6) By the series of discoveries.

22. Scan the biography in Russian. Compare English and Russian texts and make one aspect on both of them.

Людвиг Эдуард Больцман – великий австрийский физик.

Научные интересы охватывали почти все области физики и ряд областей математики. Автор работ по математике, механике, гидродинамике, теории упругости, теории электромагнитного поля, оптике, термодинамике и кинетической теории газов. Однако наибольшее значение имеют работы по кинетической теории газов и статистическому обоснованию термодинамики. Применяя статистические методы к кинетической теории идеальных газов, вывел основное кинетическое уравнение газов, являющееся основой физической кинетики. Важнейшая его заслуга – исследование необратимых процессов и статистическая трактовка второго начала термодинамики.

Был последователем электромагнитной теории Максвелла. Он провел измерения диэлектрической проницаемости газов и твердых тел и установил ее связь с оптическим показателем преломления. В 1884 теоретически вывел закон излучения абсолютно черного тела, ранее установленный Й.Стефаном экспериментально. Эта работа сыграла большую роль в развитии современной теории излучения. На постаменте памятника Больцману высечена, выведенная им формула, выражающая статистический смысл второго закона термодинамики.

В жизни Больцман был на редкость простым, мягким человеком. По воспоминаниям его учеников, он “был полон добросердечности, веры в идеалы и благоговения перед чудесами законов природы”. Его идеалом был “образ человека, забывающего о собственных интересах”.

Follow-up Activities

23. Look through the texts A & B, and the exercises of Unit II again and make notes under the following headings. Then use your notes to talk about it.

1. History of Sputtering.

2. Ionic Treatment.

3. Throughput Modes, and Markets Served by Vacuum Technology Abroad and in Belarus.

4. Benefits of Vacuum Drying.

5. Surface Preparation in Vacuum Coating.

6. Ludwig Boltzmann as a Person and Vacuum Scientist.

Unit III. Magnetron: History (part 1)

Before you start: Think it over. Agree-Disagree

“Technological progress has merely provided us with more efficient means for going backwards”. Aldous Huxley.

Note: 1894-1963, English novelist, essayist, critic

Reading, Vocabulary & Creative Practice