FR2648454A1 - METHOD FOR MODIFYING THE SURFACE OF A GLASS SUBSTRATE - Google Patents

Abstract

A method of modifying the surface of a glass substrate using the ion implantation method, characterized in that a portion of the ion implanted glass substrate is heated by using a laser beam during or after ion implantation.

Description

TECHNOLOGICAL BACKGROUND OF THE INVENTION

  Field of the Invention The present invention relates to a method of modification

  of the surface of a glass substrate using the impLan- method

  ion cation and more particularly it relates to a process for improving the surface, capable of forming a layer of

  modified surface of good quality.

Description of the Prior Art

  A method of modifying the surface of a glass substrate is already known by using the method of implanting ions. For example, a method of implanting phosphorus ions at an energy of approximately 250 KeV is already known in a glass plate containing sodium ions, followed by annealing of the glass plate at 650 ° C., in order to bind the implanted ion species and the elements constituting the glass to form a layer of phosphosilicate glass inside the glass plate, and a method for further implanting nitrogen ions over said plate at an energy of about 50 KeV and to apply annealing at 650 C in order to bond the implanted nitrogen ions and the elements constituting the glass to form a layer of silicon nitride (for example

  Japanese patent released for public inspection Sho 63-222046).

  However, in the conventional method of modifying

  tion of the surface described above, since it is necessary to apply an annealing after the implantation of ions at a softening temperature of the glass substrate or at a lower temperature, and that the reaction between the species d the implanted ions and the elements constituting the glass is not sufficient, no satisfactorily modified surface layer can be obtained. This poses a problem on the surface modification of inexpensive glass substrates for industrial use in

  as superior quality substrates.

OBJECTS AND SUMMARY OF THE INVENTION

  The present invention has been made to solve the above-mentioned problems and an object of The present invention relates to a method of modifying the surface of a glass substrate capable of forming a surface modified layer of good quality. In the method of modifying the surface of a glass substrate using the method of implanting ions in accordance with the present invention, the portions of the glass substrate in which the ions are implanted are heated by using a laser beam. during or after implantation of ions. Any condition of irradiation by a laser beam can be adaptable as long as the temperature of the surface layer of the implanted ion glass can be brought to

a higher value.

  For example, in an implanted ion layer containing a large amount of Si, the interior of the glass substrate can be heated directly using an excimer laser and a

  laser at Ar, etc. showing a high absorption with respect to Si.

  In addition, in addition to the use of high absorption laser beams in the implanted ion layer, it is also possible to heat the ion implanted layer indirectly from the glass layer by irradiation of the CO2 laser.

  showing high absorption in the glass.

  In addition, the heating can be conducted through a thin film made of a laser absorbing material placed on a

glass substrate.

  Any combination of the type of thin film with the laser beams can be used provided that the thin film on the surface of the glass containing the implanted ion layer

  is capable of being heated to a high temperature.

  For example, in the case where the Si is deposited on the surface of the glass in the form of a thin film of material absorbing the laser, the excimer laser, the Ar laser etc. showing good

  absorption in the Si film can be used as a laser.

  In addition, in the case where a film of SiO2 is formed on the surface of the glass, the CO laser showing a high absorption

  in the SiO2 film can be used.

  A semiconductor film such as Si is used preferably

  as a thin film of laser absorbing material, being

  given that the annealing of the substrate and the crystallization of the semi-film

  driver can be practiced at the same time.

  As a method for applying the heating by means of a thin film of laser absorbing material placed on the glass substrate, there may be mentioned as examples: (1) a method of irradiating laser beams after forming a thin film on a glass substrate and ion implantation, (2) a method of irradiating the laser beams while a thin film is formed on the glass substrate of implanted ions, (3) a method of irradiating the beams lasers after formation of the thin film on the glass substrate with implanted ions, etc. The laser beams can be irradiated in an optional direction and for example, they can be applied to

  the surface or back of the glass substrate.

  The laser beams can be irradiated with any force and for any time provided that the portion

  of the implanted ion glass substrate may be sufficient

  sufficiently heated and as long as the deformation of the glass substrate is not caused, etc. For example, when the laser beams are collected and spot-irradiated on the substrate, the heating of the necessary portion of the glass substrate is completed at the end.

of a short period of time.

  As the glass substrate usable in the present invention, there may be mentioned any glass substrate such as a glass substrate containing an alkali metal, a glass substrate low in alkali metal content and a glass substrate free of alkali metal. . Among these, the glass substrate containing an alkali metal and the glass substrate having a low alkali metal content are preferred because they can provide a remarkable effect of modifying the surface property which constitutes

  the main object of the present invention.

  According to the present invention, since the implanted ion layer can be instantly heated and annealed by laser beams, the necessary portion can be heated to a temperature above the softening point of the glass substrate, and therefore, the species of implanted ions and the elements constituting the glass are linked, so as to form

  a good surface modified layer.

  DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT

Example 1

  Nitrogen ions are implanted at 30 KeV by 1 x 101 ions / cm on the surface of a glass substrate, thus forming an implanted ion layer having a concentration peak at a

  0.06 µm deep from the surface of the glass substrate.

  Subsequently, the CO 2 laser (at a wavelength of 10.6 µm) is irradiated on the surface of the glass substrate. The irradiation conditions for the CO2 laser are as follows: 200 μm in beam diameter, 45 W of beam power and 1.5 m / min

scanning speed.

  Then, when the sample is measured by spectros-

  X-ray photoelectronic copy, 5 to 10 times the concentration of silicon nitride are measured in the sample irradiated by the CO2 laser compared to the sample not irradiated by the

C02 laser.

  In addition, 5 to 10 times the concentration of silicon nitride are measured and also compared to the sample having

  received a heat treatment at 400 ° C. after implantation of ions.

  It is considered that the concentration of silicon nitride has a positive correlation with the performance of preventing the diffusion of alkali metals contained in the glass substrate and it can be seen that the heating operation applied to the substrate using the laser beams in accordance with the present invention has an effect of improving the surface property of the glass substrate such as preventing the diffusion of the alkali metal.

Example 2

  OS Phosphorus ions are implanted at 100 KeV by 1 x 1017 ions / cm on the surface of a glass substrate, to form a first layer of implanted ions having a concentration peak at a depth of 0.1 pm from the surface of the glass substrate. Then, nitrogen ions are implanted at 30 KeV with 1 x 1017 ions / cm2 on the surface of a glass substrate, forming

  thus a second layer with implanted ions having a peak of concentration

  tration to a depth of 0.06 µm from the surface of the

glass substrate.

  Then, a CO2 laser (wavelength 10.6 pm) is

  irradiated under the same conditions as those of Example 1.

  Then, when the sample is measured by spectros-

  X-ray photoelectronic copy, 2 to 3 times the concentration of phosohosilicate in the first layer with implanted ions are measured and 5 to 10 times the concentration of silicon nitride

  are measured in the second imolated ion layer for the exchange

  tillon irradiated by the CO2 laser as compared to the sample not irradiated by the CO2 laser Furthermore, 5 to 10 times the concentration of silicon nitride and 2 to 3 times the concentration of phosphosilicate are measured and also compared with the sample having received a

  heat treatment at 400 ° C. after implantation of ions.

Example 3

  Silicon ions are implanted at 60 KeV by 1 x 10 ions / cm on the surface of a glass substrate to form an implanted ion layer having a concentration peak at a depth of 0.06 µm from the surface of the glass substrate and then nitrogen ions are implanted at 30 KeV with 1 x 107 ions / cm to form another layer of overlapping imolating ions

  the layer with imolated ions aue which has just been mentioned above.

  Then, an XeCL excimer laser (wavelength 308 nm) is irradiated by a pulse at a beam intensity of 100 mJ / cm2 on the surface or on the rear face of the glass substrate. When the sample is measured by X-ray photoelectron spectroscopy, the ion concentration of 5 to times is measured in the sample irradiated with the excimer laser compared to the sample not irradiated by the laser.

to excimer.

  In addition, 5 to 10 times the concentration of silicon nitride is measured and compared to a sample that received a

  heat treatment at 400 C after implantation of ions.

  As described above, it is clear that the present invention is applicable not only to a single modified layer implanted by a species of ion but also by a layer of the

  modified laminate type implanted by several species of ions.

Example 4

  Nitrogen ions are implanted at 30 KeV by 1 x 1017 ions / cm on the surface of a glass substrate to form an implanted ion layer having a concentration peak at a depth of 0.06 µm from the surface of the glass substrate. Next, a 10 nm thick amorphous Si film is formed on the surface of the glass substrate and an XeCl excimer laser (length 308 nm) is irradiated by a pulse at a beam density of

  100 mJ / cm on the surface of the glass substrate.

  Subsequently, when the sample is measured by

  photoelectronic-x-ray spectroscopy, 5 to 10 times the concentration

  Tration of the silicon nitride are measured in the sample provided with an amorphous Si film deposit and irradiated by the excimer laser compared to a sample after implantation of ions. In addition, 5 to 10 times the concentration of silicon nitride are also measured and compared to a sample having received a heat treatment at 400 C after implantation.

ions.

Example 5

  Phosphorus ions are implanted at 100 KeV by 1 x 1017 ions / cm2 on the surface of a glass substrate to form a first layer of implanted ions having a concentration peak at a depth of 0.1 µm from the surface glass substrate. Then nitrogen ions are implanted at 30 KeV with 1 x 1017 ions / cm to form a second layer of implanted ions having a concentration peak at a depth of 0.06 µm from the surface of the glass substrate. Subsequently, an amorphous Si film 10 nm thick is formed on the surface of the glass substrate and the XeCl excimer laser is irradiated on the surface of the substrate.

  glass, under the same conditions as those of Example 1.

  Then, when the sample is measured by spectros-

  photo-electronic copy X-ray, 2 to 3 times the concentration of phosohosilicate in the first layer with implanted ions and 5 times times the concentration of silicon nitride in the second layer with implanted ions are measured in the sample formed with

  the Si film amorphous and irradiated by the comparative excimer laser

  tive to the aorès ion implantation sample.

  In addition, 2 to 3 times the concentration of phosphosilicate and 5 to 10 times the concentration of silicon nitride are also measured and compared to a sample having received a

  heat treatment at 400 C after implantation of ions.

  Example 6 Silicon ions are implanted at 60 KeV with 1 x 1017 ions / cm on the surface of the glass substrate to form an implanted ion layer having a concentration peak at a depth of 0.06 µm from the surface of the glass. glass substrate. Then, nitrogen ions are implanted at 30 KeV by 1 x 1017 ions / cm to form another layer of implanted ions overlapping the layer of implanted ions just mentioned above. Subsequently, a 10 nm thick Si amorhone film is formed on the surface or glass substrate and an XeCl excimer laser is irradiated on the surface of the glass substrate under the same conditions as those

from example 4.

  When the sample is measured by photo- spectroscopy

  X-ray electronics, 5 to 10 times the concentration of silicon nitride are measured in the sample formed by the amorphous Si film and irradiated by the excimer laser and compared with a

  sample after ion implantation.

  In addition, 5 to 10 times the concentration of silicon nitride are also measured and compared to a sample having received heat treatment at 400 C after implantation of ions.

Example 7

  Nitrogen ions are implanted at 30 KeV by 1 x 10 7 ions / cm on the surface of the glass substrate to form an implanted ion layer having a contraction peak at a depth of 0.06 pm from the surface of the substrate glass. Next, a SiO2 film having a thickness of 1 µm is formed on the surface of the glass substrate and then irradiated by a CO2 laser (wavelength 10.6 µm). The conditions for irradiating the CO2 laser include the following: 200 μm in beam diameter,

  45 W of beam power and 1.5 m / min of scanning speed.

  Subsequently, when the sample is measured by

  X-ray photoelectronic spectroscopy, 5 to 10 times the concentration

  silicon nitride are measured in the sample

  formed with the SiO2 film and irradiated by the C02 laser compared

  ratively to the sample after implantation of ions.

  In addition, 5 to 10 times the concentration of silicon nitride are also measured and compared with a sample having received a heat treatment at 400 C after implantation of ions. Although the laser beam is irradiated on the surface of the glass substrate in the examples mentioned above, the irradiation by the laser beam can be conducted in any direction, for example on the rear face not limited to the surface of the substrate glass. In addition, the shape of the substrate in

  glass can optionally be not limited to the substrate.

  According to the present invention, since the implanted ion layer of the glass substrate can be instantly heated to an elevated temperature without softening of the entire glass substrate, the bond between the implanted ions with each other and / or the ion and the ions implanted inside the glass can be improved to obtain a layer modified in

good quality surface.

Claims (4)

  1. A method of modifying the surface of a glass substrate by using the ion implantation method, characterized in that a portion of the glass substrate with implanted ions is heated by using a laser beam during or after the implantation of ions.   2. A method of modifying the surface of a glass substrate according to claim 1, characterized in that the heating is applied using a thin film of a material   absorbing the laser arranged on the glass substrate.   3. A method of modifying the surface of a glass substrate according to claim 1 or 2, characterized in that the   heating temperature is equal to or above the boiling point smoothing the glass substrate.   4. A method of modifying the surface of a substrate   glass according to any one of claims 1 to 3, charac-   terized in that the glass substrate is a glass substrate containing an alkali metal or a low content glass substrate made of alkali metal.