DE2708652A1 - INTEGRATED OPTICAL CIRCUITS AND METHOD OF MANUFACTURING THE SAME - Google Patents

Description

Integrated optical circuits and methods of making the same

The invention relates to thin film assemblies or elements and, more particularly, to thin film optical elements .

The use of light rays, in particular LASER rays, as information carriers has already been proposed, however, the practical application of the principle on a commercial scale, because of the "unwieldiness" of the existing equipment such as lenses, prisms, mirrors, etc. Difficulties that arise in practice Problems of the reliable, convenient and spatially concentrated execution of different switching functions such as modulation, filtering, coupling, switching, reception or detection, etc. To fix this So-called integrated optical circuits have become problems

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(OIC) proposed. These essentially comprise a planar thin-film optical waveguide, the one Forms light path of suitable refractive index on a suitable substrate. To "lock in" a ray of light Within the waveguide boundaries, the refractive index of the optical waveguide must be such that Total internal reflection occurs at the boundary surfaces of the conductor, so that the beam within the optical waveguide economical, without undue loss of light (by emission from the waveguide) within the guide can be reflected.

Typical cross-sectional dimensions for OIC waveguides range from u-parts to a few ju and unevenness in the boundary of the waveguide must therefore ^{not exceed a few 100 A (depending on the difference in the refractive index 1} between the waveguide and the substrate). That is, extreme accuracy in the deposition or etching of the waveguide is essential.

Some methods of depositing a suitably thin layer have been proposed and those The theory of thin-film OICs is described, for example, in "Integrated Optics" by Chang, Muller and Rosenbaum, Laser Applications 2, 227 ff., Academic Press, Ine 1974 described.

The present invention is now particularly concerned with methods of fabricating thin film OICs as well as methods for modifying such circuits or circuits and their application.

The method according to the invention is essentially based on the deposition of at least one component

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of the OIC using a Langmuir Film technique. Langmuir movie Techniques are known; they involve the passage of a substrate through a thin, preferably monomolecular, Layer of a film-forming material provided on the surface of a carrier liquid. It is so possible Obtain films of material without the evaporation of large volumes of solvent required for this formation were; tearing of the film as a result of the release of solvent is avoided. 10

The technique chosen by the applicant, hereinafter simply referred to as Langmuir technique, consists essentially of the following:

The carrier liquid is preferably inert for the film-forming material, that is, it is not chemical Reactions with the material of the layer or the substrate under the conditions of the invention Procedure (although it may occasionally be desirable to include materials, possibly in solution, which do not have an adverse effect on the film, but with it, for example, changing the ionic Composition can react). The serving as a base or carrier liquid is also usually not be a solvent for the film-forming material, although some solubility not necessarily is of great damage as long as the layer of film-forming material does not destroy it or its Education is prevented. The liquid can be organic or inorganic; usually the application an aqueous liquid, expediently water, is preferred. The presence of certain inorganic ions in an aqueous carrier liquid proves to be beneficial for the stability of the film-forming Layer, with ions being carried along by the film during deposition white υ. the composition in a desired one

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Way can influence.

So it has occasionally been found to be desirable in a carrier liquid formed by highly purified water Metal ions, expediently cadmium ions, in sufficient concentration for a link to introduce hydrophilic end groups of adjacent molecules of a film-forming material based on fatty acid. Other ions can be applied in a similar manner where they have the required properties and it has been found beneficial to keep the pH of the carrier liquid slightly acidic (in the region of 5.3) to bring the ionization of the metal salt to an optimal level.

The creation of the thin layer of the film-forming material on the surface of the carrier liquid is most conveniently carried out by placing a suitable volume of a solution on the surface of the liquid film-forming material is applied in a volatile solvent that interacts with the carrier liquid under the process conditions is immiscible and evaporates after the solution has been applied to the surface of the liquid. The concentration the film-forming material in the solution is chosen so that the evaporation of the solvent leaves a layer of the desired thickness (usually monomolecular) on the surface of the carrier liquid. The preferred film-forming materials according to the invention, together with an aqueous carrier liquid are those with a molecule that has both hydrophilic and hydrophobic components comprises, of which the hydrophilic components tend to be immersed in the liquid from the surface, while the hydrophobic components tend to remain unwetted and protrude from the surface.

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The film-forming material is transferred to the substrate by immersing it in the carrier liquid and removing it again so that a continuous layer of the film-forming Material (referred to herein as "Langmuir Film" for convenience) adheres to the surface of the substrate. Means must be provided for maintaining the integrity of the layer on the liquid, for example comprising a rudder or a paddle, preferably controlled by a microbalance, which consistently measures the pressure of the layer on the carrier liquid and then by "sweeping up" the pressure on the Molecules located on the surface responds, so that the layer does not tear. This characteristic of maintenance the tension or pressure on the layer is necessary to produce an aligned continuous film important on the substrate.

The rate of passage of the substrate through the layer is preferably slow in the area of 3 mm / min, for the first 2 or 3 films, although higher speeds, up to about 30 mm / min, may be acceptable for subsequent layers.

The temperature of the aqueous carrier liquid is preferably 21 ± 0.5 ^° C

The substrate employed in accordance with the invention can be any suitable material, many of which are known and are described in the literature. Preferably the substrate will be polar. As an example, glass, e.g., soda glass and borosilicate glass and preferably quartz can be mentioned, although numerous other materials are known in the art and can be used if they have suitable properties. The substrate

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surface may require treatment to make it compatible with the film being deposited; for example, it has been found useful to treat quartz with alkali, eg NaOH, at pH 11 to 12 in order to give it an optimal polarity for the deposition of long-chain fatty acids. For optical purposes it is desirable that the substrate does not have a high proportion of absorption centers and it must be capable of being polished to form good surfaces. A homogeneous material, such as a high-quality quartz glass (high quartz glass \ is desired.

The dimensions of the substrate are not critical, but are determined, for example, by the dimensions chosen of the intended OIC. Typically The substrate can consist of a quartz plate with a side length of a few cm and a thickness of the order of 1 mm.

The thickness of the Langmuir film can be adjusted as desired by repeated treatment of the substrate in the described Manner, thereby depositing additional layers on the substrate. Although the conventional Langmuir Film Techniques would result in films with an unacceptable number of breakage or crack type defects found that by carefully controlling the process conditions it is possible to apply several hundred layers (300 or more) with a few defects to deposit or apply, which makes the fabrication of (fiber optic cables from 0.7 to 1.5 / rev.

Suitable materials for the OICs include any or all materials with suitable optical properties Properties applicable as the film component in the Langmuir technique described above. Particularly organic materials and special materials are suitable

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rials which are to be mentioned, would be, for example, fatty acids, particularly straight-chain fatty acids having 12 to 20 carbon atoms such as stearic acid, peanut or arachidic acid and salts thereof such as cadmium salts, anthracene-C ^ - C ^ 2 ~ ^car ^ ^ons äuren and Compounds as mentioned in DT patent application P 26 37 099.0.

These materials are particularly useful for OIC applications because of the ease of choosing an appropriate dielectric film index ¹ by selecting an appropriate chain length, the ability to entrap metal ions to "fine tune" the index of refraction, and the ease with which the film thickness passes through the Langmuir technique can be controlled.

It is to be noted that one particular material is considered to be particularly suitable for its intended purpose is selected. Organic materials exhibit valence type bonding because of their generally low densities and valence type bonding usually relatively low optical losses in the visible range of the spectrum (although of course the OICs are not limited to the application of visible radiation).

The radiation applied can be of the ultraviolet

to the infrared range (of course using waveguide materials and dimensions suitable for the wavelength of the radiation chosen). That is, the wavelength of the radiation can vary between about 4000 Å and about 10 μ, but visible radiation and radiation with a wavelength up to 0.9 μ »from 1.15 to 1.3 μ and from 3.39 to 9 μ favored or preferred.

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It has been found that most of the optical loss in amorphous organic films is due to the Scatter (caused by "molecular disorder" and "inhomogeneity") and non-uniformity decreases originates from the deposition technique. The techniques described here are particularly advantageous in this regard, since they have an inherent tendency to deposit essentially ordered layers of material (which in their Short-range order characteristics come close to the single crystal), so that a product with reduced scattering properties can be expected to be obtained. It is possible that losses of less than 1.0 dB cm can be routinely expected in such films. A Another advantage of these films is that their refractive index is so due to the selection of the chemicals that make them up can be controlled to suit a particular application, which is an important feature of the Manufacturing OICs is. For example, the incorporation of metal ions into the film can affect its index of refraction. The effect of such a change can of course easily be determined by simple experiment.

Although planar waveguides are widely studied, and the present invention components or arrangements that are topographically Use defined waveguide components and connection systems, preferred for many purposes. A limitation of the rays in the lateral plane of the waveguide means a modification of the waveguide properties in a very precise way in selected areas of the film and the edge sharpness and accuracy The placement of the guiding boundary in the flat film are extremely important parameters. Here, in turn, the high degree of molecular

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orientation, as it is typical for the present Langmuir films, contribute to the sharpness of the edges.

A particular application of Langmuir films of the invention in an OIC is in waveguide cladding (as shown in Figures 2-6) wherein a layer or film of a suitable "superfine" material is deposited on the waveguide itself If the cladding has a refractive index different from that of the waveguide, it will modify the properties of the waveguide is the electric field distribution of the propagating wave into the cladding (as shown schematically in Figure 9). In such a case the cladding will carry a significantly greater proportion of energy (compared to the air superstrate structure). The result is an increase in the normalized propagation constant (ß11) of the sic h propagating wave. There are two possible configurations for the superstrate: (i) in which the refractive index> β / K for the propagating wave and (ii) in which the refractive index of the cladding is < β / k. In case (i), the electric field changes sinusoidally in the cladding in the direction normal to the conductive film. In case (ii) the electric field decays exponentially into the cladding. The sinusoidal electric field in the cladding will carry considerably more of the conducted energy than the evanescent field and will therefore produce a far greater modification in the propagation constant. The feature of the new technology, according to which it is possible to adjust the film thickness and the

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Precisely controlling the refractive index shows a particular advantage here, and it is found that a particular one suitable arrangement format such a prefabricated waveguide with a (by applying some Monolayers) induced relatively low ß / K disruption.

Diagram 10 shows curves for the normalized propagation constant as a function of the cladding thickness, as they result from the simple waveguide theory based on a dielectric plate.

The accuracy with which the wave propagation constant can be set, is evident from the correspondence between the measured values and the mathematical prediction.

The propagation constant of the waveguide can be changed in a controllable manner so that the Example two adjacent waveguides that are close together but not "matched" (i.e., different- borrowed propagation constants), as outlined for example in Fig. 6 of the attached drawings by the application or application of a suitable modifying plating to one or both of the Waveguides can be "tuned" so that a Enables energy coupling from one conductor to the other will. An alternative use is to use a superstrate plating film for reduction the propagation constant of a wave ("mode") of a conductor to a value below the cut-off point, so that the energy transported in this wave can be released or removed from the conductor.

Thus, in accordance with one embodiment of the invention, a component for an OIC is provided that includes a Langmuir film. According to a second embodiment

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a substrate having a waveguide deposited thereon and characterized by a Langmuir film is provided. Yet another embodiment of the invention includes an OIC component having a waveguide and cladding deposited thereon identified by Langmuir film is drawn.

In plating applications, the thickness of the plating affects the waveguide energy contained in the plat can be transported and thus the extent to which in which the cladding affects the waveguide, while the index of refraction of the cladding determines how much "normalized delay" (i.e. the degree of the decrease in velocity per unit of layer thickness of the waveguide plating) occurs. The importance of the precise molecular targeting capabilities of the new technology inherent in the production of such claddings will be understood below:

The fact that the new Langmuir films consist of regularly and precisely aligned molecules or molecular structures makes them photoresist or Photoresist material particularly useful, in which, thanks to the sharp edge effect, particularly sharp and precise borders tongues can be achieved. This is a peculiarity which makes such films useful not only for the production of waveguides, but also in many other areas where relatively thin, highly defined photoresist material (potential) is required. So it is considered to deposit a Langmuir film of suitable radiation-polymerizable material on a base or to deposit and to expose imagewise, whereby the exposed parts of the film polymerize (see Fig. 3). the Removal of the unexposed parts of the film any suitable measures leaves a photo

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paint residue with a precisely defined potential (Fig. 4). Such techniques can be used, for example, in the etching of waveguides, in waveguide plating or for related components of OICs, but they can also be used, for example, in lithographic reproduction processes for the definition of patterns of miniaturized electronic components where "sub-micron ¹¹ resolution is required as well as for diffraction gratings, etc. Usually, for such processes (as above), preference is given to using materials which polymerize with only a slight change in area or in such a way that dimensional changes are foreseeable and can be permitted.

Components or arrangements according to the invention are illustrated schematically by the attached perspective Illustrations of which Fig. 1 shows a planar light guide made in accordance with the invention is. Figure 2 shows a "topographical" waveguide with the actual waveguide and a cladding layer, which can expediently be applied by the present Langmuir technique. 3 and 4 show arrangements with a modified structure. Fig. 5 shows a vertical section through a Planar film conductor coupling. 6 shows a plan view of a "topographical" conductor coupling.

According to the drawings, a Langmuir film (1) is deposited on a substrate (2). The waveguide (3) will either in the present Langmuir film or in another component (4) of the assembly. The entry a (light) beam in the waveguide and its exit from this can expediently using by prisms (5), albeit using smooth couplings or any other suitable method can be. If more than one waveguide

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AS

If necessary, as shown in Figure 5, one or both of the planar components comprising the waveguide can be deposited in accordance with the present Langmuir technique and will be useful by means of a spacer or a spacing (6) of suitable dimensions and composition from one another which can optionally also be deposited by the present Langmuir technique.

It has been found that in order to obtain Langmuir films of high optical quality, control of certain aspects of the deposition process is critical:

(a) using an impurity-free sub-phase and purified film material;

(b) the pressure / molecular area relationship;

(c) the pH of the subphase; 20th

(d) the temperature of the subphase;

(e) the rate of deposition and pressure change in the droop during deposition

Monolayer.

(a) Any other molecules that are in the subphase as impurities can be in the film structure can be incorporated. your attendance In the structure, the peculiarity of the polar / non-polar orientation of the subsequent layers can interfere or modify and lead to wetted areas that are included in the multilayer film. The trapped water can cause splitting of the film or

Cause pinholes or the other molecules

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can be used as absorption or scattering centers in the waveguide film works. It is therefore important that the tank or container be extremely clean, the footage extremely pure and the sub-phase water has been distilled several times (e.g. in a quartz apparatus, to exclude contamination; typically acidic and alkaline potassium permanganate distillation stages are used provided with neutral distillation to remove organic impurities). 10

(b) At low pressure, the film molecules are loosely packed and take up a large surface area, ie they are separated from one another by water rising to the surface. If the molecules remain loosely packed, the film deposited on the substrate will often have water-filled molecular voids. If, on the other hand, the molecules are packed too tightly, the film on the subphase can "collapse" ¹¹ or "slide together" to form agglomerated areas that are several layers too thick. The monolayer on the subphase should therefore be kept under such pressure , in which the molecular surface area remains effectively constant with a larger change in pressure, so that small changes in pressure caused by immersion and entrainment of the substrate do not cause the film to break or tear or fold up.

(c) The degree of ionization of a fatty acid in the subphase depends on the pH of the solution. One strong basic subphase will lead to increased ionization and thus the conversion of the fatty acid into salt increase; from the increased molecular polarizability (caused by metal ions trapped in the film caused) an increased film refractive index results. It also has a relatively high pH

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improve the film / substrate adhesion. It has been found that both the index of refraction and adhesion are satisfactory for films deposited at pH values between 5 and 7. These conditions gave adequate film deposition on most metal oxide substrates (e.g. Al ₂ O ^, MgO), however they were not as satisfactory for fused quartz

-Substrates that have been treated with advantage by immersion in an alkali solution to modify the surface. Such a process is described by Bucher in the Zeitschrift für Physikalische Chemie, new part 65 . (1969) pp. 152-169.

(d) The condensation of the molecular layers to form a monolayer on the sub-phase surface becomes easier by lowering the temperature. However, the low temperature can increase the viscosity of the monolayer, making it more "brittle". On the other hand, high temperatures can lead to expansion and eventually high enough thermal forces to overcome the rather weak Van der Waals forces that hold the molecules together. This can increase the solubility of the molecules and make the layer unstable. The preferred temperature range for the deposition of cadmium stearate films is from 19 to 22 ^° C., but those skilled in the art will be able to determine the optimal temperatures for other materials without difficulty.

(e) It is important that the layers applied at the beginning are formed as well as possible, since defects can occur can reproduce in these layers in the following layers. To ensure good adhesion the initial layers are preferably deposited at low immersion and entrainment speeds,

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After a few layers have been applied, the speeds to be increased somewhat. Low speeds are expediently of the order of magnitude of 3 mm / min, higher speeds at e.g. 24 to 30 mm / min.

The film must be maintained in the condensed phase during deposition so that the molecules are neither too loose nor too tightly packed.

In Fig. 8, the pressure change is shown during immersion and entrainment of the substrate. The working point (at approx. 30 mg / cm) is chosen so that the pressure change remains between 25 and 35 mg / cm. The immersion and The entrainment speed affects the amplitude of the disturbances and it is precisely this factor that determines the maximum Substrate speed determined.

Preferred deposition conditions are: Temp .: 19-22 ⁰ C; Metallionen_konz .: 2 χ 10 ~ ³ mol CdCl ₂ ; Sub-phase: water; 4 χ distilled; Substrate: quartz glass; Treatment of the substrate: stay in alkali; Deposition rate: 3 mm / min at the beginning and 24 mm / min after a few layers.

Typical films have the following properties: Conductor A

Number of layers - 281;
Modes - TE _Q , TM _Q ;

mean loss measured along worst case V / ege;

Defect level - 6.2 dB / cm TM, 5.1 dB / cm TE _Q minimum loss - 1.0 dB / cm

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Reproductive path length - 20 mm. ♦

Head B

Number of shifts - 221
Fashions - TM _Q

mean loss - 3.6dB / cm TM _Q reproductive path length - 20 mm. *

* The length of the propagation path is only limited by the size of the substrate.

Using the Langmuir film technique according to the invention it is possible to obtain OICs with isotropic refractive indices and make waveguide film thicknesses that can be controlled with great precision. to typical controllable factors include:

(a) The refractive index of the waveguide film can be determined by selecting the length (e.g. the CH ₂ chain in the molecule) for molecules of the simple long chain type, for which the palmetic acid, stearic acid, arachidic acid series is typical (but not limiting). be set;

(b) the incorporation of metal ions into the hydrophilic end

replacing hydrogen;

(c) the application of materials in whole or in part can be polymerized on the subphase;

(d) Variation of the molecular structure, e.g. number of aromatic Rings;

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OK

(β) the film thickness obtained by controlling the number of deposited layers can be controlled.

Since the molecule length can be set within parts of an angstrom, the total film thickness can be set to, for example, about 20 Å in 5000 Å.

The consequence of the accuracy attainable by the technique described is that it can is, the propagation constant of the waveguide (the speed of the transmission of energy within of the limited area) to one part in 1.5 x 10 ^ parts or better to specify.

Details of the apparatus (shown schematically in Figure 7) and the coating process used when carrying out the invention according to the examples are given below:

A rectangular glass container 1 was filled with water 2 to a height of 6 cm. Cadmium arachidate 3 was distributed on the water surface, filling the area between the two glass plates 4 and the gravity-controlled barrier 5. The compressive force on the molecules was determined by monitoring surface tension of the film was measured by means of a Wilhemy balance (plate type). The container came with a Cover 6 covered to exclude dust from the environment. The entire system was vibration-free on one mounted table 7 to prevent "slipping" of the film by vibration. the Movement of the substrate 8 (the speed of which was kept as constant as possible) was carried out by a Linear motion drive controlled via a reduction gear has been actuated, whereby the direction of movement is controlled by reversing microswitches on the frame.

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was controlled. The characteristic of constant immersion and Driving speed and freedom from vibrations are very important for the production of regular films.

The invention is explained below using examples.

example 1

The flat surface of a normal glass plate (soda / lime glass) was lapped with progressively finer carborundum powder and then polished with progressively finer diamond particles (suspended in oil) on a plate with a soldering tin surface on an optically flat polishing machine and finally with a polyurethane foam bollard disc and a chemical etching abrasive ("Syton") until the surface was optically flat to about half a wavelength and smooth to about 50 Å. The surface was then carefully cleaned to remove any polishing materials and a glass layer waveguide (Dow-Corning aluminoborosilicate 7059) was formed thereon by radio frequency spraying (see "Thin Solid Films" 26 (1975) pp 25-51). In the sputtering or spraying process, argon gas mixed with 20% oxygen was introduced into the vacuum chamber (the oxygen was added to replace oxygen removed from the target glass during the sputtering). A lack of oxygen in the deposited film increases the refractive index of the film compared to that of the target solid material, so that a limiting technique as described in the referenced article can be used to control the refractive index of the film.

A Langmuir film was then deposited on the waveguide by repeated vertical dipping

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of the plate in water with the entrainment of a monomolecular layer of cadmium arachidate on its surface until a Layer of 200 molecules thick was built up.

Example 2

A thin layer (about 1000 to 5000 Å) of titanium was sprayed or sputtered onto a flat surface of a lithium niobate crystal (the metal was sputtered into a pure argon atmosphere (to prevent oxidation) from a metal target attached to a water-cooled base). The coated substrate crystal was then placed in a diffusion furnace and the temperature (at a rate of no more than 20 ^° C. per minute to prevent cracking of the crystal) gradually increased to 1100 ^° C. The metal was then allowed to diffuse into the crystal for 6 hours, after which the crystal was ^{cooled to room temperature (at no more than 20 °} C. per minute). A very thin film (50 Å) of aluminum oxide was then deposited on the metal to improve its adhesion to the Langmuir film material which was applied essentially as described in Example 1.

Although the use of a normal glass as a substrate was described in Example 1, any other suitable glass can be applied in a similar manner, such as flint glass and amorphous quartz glasses, etc.

Numerous inorganic crystals such as lithium tantalate, Quartz, sapphire, etc. can be used as an alternative to the crystal of Example 2, while the substrate alternatively can consist of a solid inorganic amorphous material such as an oxide such as aluminum oxide, Magnesia or silicon oxide.

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The dimensions of the different components, of substrates, etc. and the thicknesses of the deposited films can vary within limits known in the art can be determined as desired, however, they are determined by, among other things, their respective refractive index and those the related and neighboring components.

Example 3

Waveguides were deposited as described in Example 1, but using cadmium stearate as Langmuir film material to examine the influence of a change in the pH value of the sub-phase (which is formed by water) det). The refractive index and the thickness of the resulting films were measured. The following Results were achieved:

Movie thickness
I. Refractive index _; e-beam At
isotropy Refractive index
the forest middle
value
e-beam PH A.
B.
C.
D. 1750
2300
2500
3100 o-ray 1.5472
1.5435
1.5468
1.5448 0.0373
0.0358
0.0370
0.0366 middle
value
o-ray 1.5475
i 0.0024 5.3 E.
F.
G 2580
3300
5400 1.5099
1.5077
1.5098
1.5082 1.5704
1.5663
1.5701 0.0442
0.0402
0.0450 1.5107
+ 0.0005 1.5681
+ 0.0173 5.6 1.5265
1.5261
1.5251 1.5266
+ 0.0031

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This table shows the effect of increasing the pH of the subphase on the properties of a typical Langmuir waveguide - as can be seen, the refractive indices of both the "e" and "o" rays increase significantly. The change in the refractive index ¹ results from a differential inclusion of cadmium ions in the stearic acid film, which in turn arises from the controlled ionization of the OH ends of the stearic acid molecule resulting from the pH difference. 10

The possibility of precise control of the refractive index ¹ of waveguides and coating layers is illustrated as follows:

An arrangement or device as shown in Fig. 5 can be made essentially as follows are: A quartz glass substrate is, as described in Example 1, prepared and dusted with a layer of amorphous aluminum oxide (using a technique similar to in "Thin Films" 26, (1975) pages 25-51).

This layer is referred to as conductor ^M a "in Fig. 11 (a). The aim is to establish a refractive index ¹ of 1.65 and a thickness of 0.23 µm for the propagation of a TE wave (TE). A quartz glass - Spacer layer is then sputtered over layer "a". Another layer of alumina is then sprayed onto the spacer layer (waveguide "b" in Figure 11 (a)), the intent is to make "a" and "b"identical; however, since this is not possible (due to the difficulty in depositing precise layer thicknesses by sputtering), the properties can be adjusted by depositing a Langmuir film plating.

To create a waveguide coupling (i.e. a device that connects a power circuit or a power

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transition from head "a" to head "b") the ß-values of both conductors must be the same. A Langmuir coating can be applied over the top layer for this so as to increase their constant of propagation. If the two conductors in terms of propagation constants are the same over a few cm conductor length, the energy "switches" or jumps continuously back and forth between the conductors over the coupling length. The Langmuir coating enables an interruption of this oscillatory movement by the end of the coating after a length necessary for equalization the layers are sufficient for complete energy transport or a shorter length can be deposited which enables the transport of a determinable fraction of the energy of the excited conductor, while the rest of the energy remains in the excited conductor. Fig. 11 (b) shows the detailed coating characteristics, which is necessary for an alignment of the structure to (a), the length L being selected in this way becomes that the required energy transport can be achieved.

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Claims (1)

TlEDTKE - BoHLINe - KlNNE - GflüHE "· -« ■ * Dipl.-Ing. Tiedtke OTflQCCI Dipl.-Chem. Bühling 2708652 _D £, ._ _lng . _Chins Dipl.-Ing. Group Bavariaring 4, P.O. Box 20 24 8000 Munich 2 Tel .: (0 89) 53 96 53-56 Telex: 5 24 845 tipat cable. Germaniapatent Munich May 3, 1977 Patent application P 27 08 652.8 Imperial Chemical Industries Ltd. B 7989 / ICI case Z / Q 28598/29032 Claims 1. Integrated optical circuit component, characterized by a Langmuir film .- ..,,., ¹ I. 2. Component according to claim 1, characterized by a Substrate with a waveguide deposited on it, which surrounds a Langmuir film. 3. Component according to claim 1, characterized by a waveguide with a plating or coating deposited thereon, which includes a Langmuir film. 4. Component according to one of the preceding claims, characterized characterized in that the Langmuir film comprises a straight chain fatty acid or a salt thereof. 5. Use of the component according to any one of claims to 4 in a layered product consisting of one 709836/0827 Dratdntf Bank (Munich) KIo. 3939 844 PosUchKk (Munich) account (70-43-NM ORIGINAL INSPECTED Substrate with Langmuir film of radiation polymerization material deposited thereon, especially as a lithographic plate. 6. A method for producing a product (component, sheet material or plate) according to one of the preceding claims, characterized in that a substrate is so formed by a layer deposited on a liquid sub-phase of a Langmuir footage is moved that a Langmuir Film is deposited on it. 709836/0827