CS217241B1 - Method of making the anorganic amorphous or polycrystallic thin layer - Google Patents

Description

The invention relates to a process for the production of an inorganic thin amorphous or polycrystalline layer or an array of such layers.

In the current mock technique, various processes are used in the production of thin inorganic layers, such as vapor deposition of solids under reduced pressure, sputtering, preferably sputtering in a reactive atmosphere, thermal decomposition of gaseous compounds, and other processes. The disadvantage of such methods is either the energy consumption and / or the necessity to work at high temperatures, or the fact that they only produce layers that have inferior physical properties and do not meet the requirements. Methods for making hetero-9 transitions are also known in which the starting materials are contained in a confined space under reduced pressure of 10 to 10

300 Pa causes a glow discharge, for example at a frequency of 13.56 MHz. However, this method has been solved and is only used for some special purposes.

It has now proved to be advantageous and necessary to provide a method for producing thin films which have improved physical properties over the known state of the art (Proceedings of the 4th International Symposium on Plasma Chemistry Zurich 1979, Ed. S, Vepřek and J. Hertz). properties, in particular where it will be possible to vary electrical conductivity values over a wide range from those typical of the insulators to those corresponding to superconductors. In addition, layers are required which have the desired edge position of the optical absorption, possibly having a high hardness and a high abrasion resistance; There is also a need for substances which can be used as diffusion barriers to prevent the diffusion of materials separated by this barrier.

This object is achieved by the invention of a process for the production of an inorganic amorphous or polycrystalline thin film of 0.001 to 50 microns in thickness or an array of such layers by applying a glow discharge in a confined space under reduced pressure to gaseous or liquid starting materials. The present invention relates to a process in which A + B, A + C or A + B + C is the starting material of formula A wherein B is XY _m wherein X is antimony, molybdenum, niobium, tantalum, thallium , uranium, vanadium, bismuth or tungsten, and Y represents a fluorine or chlorine atom, wherein m is a natural integer ranging from 3 to 6, wherein B represents a compound of the general formula z (K _n L _Q ) in which K denotes an arsenic atom , boron, nitrogen, phosphorus, germanium, silicon, selenium, sulfur, tellurium or carbon, L is a fluorine, chlorine or hydrogen atom, z, n and n are integers from 1 to 10, n is 1 to 10 2 _o is equal to 1 to 4, wherein the groups z (K _n L ₀ ) where z is equal to 2 to 10 differ in chemical composition, further wherein C stands for argon, nitrogen, neon oxygen, hydrogen or a mixture of two to five under a pressure of 10 to 500 Pa a 0 to 10 ^ Hz frequency.

The invention is based on the finding that, depending on the operating conditions selected, either amorphous or polycrystalline alloys or non-metal compounds with antimony, molybdenum, niobium, tantalum, thallium, uranium, vanadium, bismuth or tungsten can be produced at very low power consumption. Said metals may also be doped with non-metals or their alloys.

The advantage of the method is the fact that in comparison with existing gas or phosphine PH-borane, B ₂ ^H 6 J ^sou compound of the formula XY _m safer and more convenient work standpoint.

Protective coatings can also be applied to substrates of complex construction shapes, which has not been achieved by known methods such as reduced pressure vapor deposition or sputtering. Compared to the thermal decomposition process used hitherto, this method has the advantage that substrates of substantially lower temperatures, such as 20 ° C and 30 ° C, can be used, which is much less than earlier temperatures of 600 ° C. to 1000 ° C.

The advantages of this solution are evident from the following examples which illustrate the invention without limiting it in any way.

Example 1

The reaction is carried out in a reaction chamber of reduced pressure, in which a glass or metal substrate is placed on one electrode, preferably on an upper ungrounded anode of 8 1/2 cm diameter, and about 1 cm below the anode, a second electrode - cathode - of diameter 8 cm. A gas mixture containing SiH 2 silane and antimony fluoride SbF 3 in a SiH 2: SbF 3 volume ratio of 2 to 30 is fed into the reaction space at a flow rate maintained by the pump system at 1 to 100 stand.cm 3 / min. preferably at 2 SCCM. The cathode is fed with a high frequency energy of 1 to 20 MHz at a power of 0.5 W / cm. Before the discharge ignites, the pressure of the gases in the reactor is 10 Pa; when the discharge ignites, the pressure in the reaction space rises to about 40 Pa. During the reaction, the temperature of the pads was maintained at 300 ° C, with the amorphous silicon-antimony alloy increasing at a rate of about 1.3 microns / hour.

The composition of the resulting alloy is controlled by the SiH 2: SbF 2 ratio. After completion of the work, the reaction space is purged several times with argon and the space is depleted again.

The electrical conductivity of the alloy at normal room temperature and in the dark varies between 10 ^{11 11} to 10 ^{2 2} ohms ^-1 , cm ^- odpor the resistance of the alloy is light sensitive, the position of the absorption edge is shifted from 650 to 1,200 nanometers, depending on the ratio of SiH2 to SbF2.

Example 2

The procedure is as described in Example 1, except that a mixture of (SiH4 + SiF4) is used instead of silane at a SiH2: SiF2 volume ratio of 0.01 to 10. This modification facilitates the formation of the alloy and increase the efficiency of doping.

Example 3

The procedure is as in Example 1, except that a mixture of methane and tungsten fluoride WFg is used instead of silane and antimony fluoride. The pads have a temperature in the range of 0 to 800 ° C. The resulting alloy of the formula WC having variable values x y x and y is characterized by high hardness and abrasion resistance.

Example 4

Under the same operating conditions as described in Example 1, a mixture of ammonia, niobium fluoride NbF 4 and nitrogen was introduced into the reaction space. A superconductor Nb _x Ny with variable values of x and y is formed.

Example 5

Under the same operating conditions as described in Example 1, a mixture of SiO 2 silane and NbF 4 is added to the reaction space. The superconductor Nb2 Si is formed.

Example

The procedure is as described in Example 1 except that a mixture of niobium fluoride NbFb and oxygen is introduced into the reaction space. A dielectric layer of NbgOj is formed.

Claims (1)

A process for producing an inorganic amorphous or polycrystalline thin film of 0.001 to 50 microns thickness or an array of such layers by gaseous discharge in a confined space under reduced pressure on gaseous or liquid starting materials, characterized in that the starting material of general formula A + B, A + C or A + B + C, wherein A is 2Y _m wherein X is antimony, molybdenum, niobium, tantalum, thallium, uranium, vanadium, bismuth or tungsten, and Y is fluorine or chlorine, wherein m is a natural integer ranging from 3 to 6, wherein B represents a compound of the general formula z (K _n L ₀ ) in which K denotes arsenic, boron, nitrogen, phosphorus, germanium, silicon, selenium, sulfur, tellurium or carbon , L is fluorine, chlorine or hydrogen, z, na are natural integers wherein z has a value in the range of 1 to 10, n is equal to 1 and 2 and is equal to 1 and 4, of the general formula z (KL) where z has a value in the range of 2 to 10 differing in chemical composition, further wherein the symbol C denotes argon, nitrogen, oxygen, neon, hydrogen or a mixture of two to five of these, up to 500 Pa causes a glow discharge with a frequency in the range of 0 to 1θ ° ° Hz.