CN1131847C

CN1131847C - Optical element molding die and method of manufacturing the same

Info

Publication number: CN1131847C
Application number: CN97109525A
Authority: CN
Inventors: 平林敬二; 宫崎直; 大森正树
Original assignee: Canon Inc
Current assignee: Canon Inc
Priority date: 1996-02-16
Filing date: 1997-02-14
Publication date: 2003-12-24
Anticipated expiration: 2017-02-14
Also published as: KR100211473B1; KR19980068136A; CN1168355A; JPH09278462A; MY128189A

Abstract

This invention provides a molding die of optical element which has high hardness and excellent surface smoothness and durability and does not cause melt sticking of a glass. The molding die produces a glass optical element by press forming, forming a specified TaN thin film contains lithium element or its compounds on at least the forming face of the die so that the thin film acts as a release layer.

Description

Forming die for optical element and preparation method thereof

The present invention relates to make glass optical component, such as glass lens and the used forming die for optical element of prism, and manufacture the method for this mould by compression moulding.

Utilize compression moulding to manufacture optical element, glass lens for example, without any need for polishing step, this manufacturing technology do not need tradition make in required complex process, the making that makes optical element is not only simply but also cheap.Especially in recent years, this technology begins to be used in the making of prism and other specific glass optical element and lens.

The moulding stock that is used in this glass optical component compression moulding needs high rigidity, high heat impedance, good release stress characteristics and good minute surface workability.Usually, select for use metal and pottery as moulding stock, in various making methods, with above-mentioned any coated materials molded surface.

For example, Japan postpones publication No.49-51112, and 52-45613 and 60-246230 propose to use respectively 13Cr Ma Shi steel, SiC and Si ₃N ₄And be coated with the material that one deck is mixed with the carbide adhesive linkage of rare metal.Japan postpones publication No.61-183134, and a kind of thin diamond or the carbon film layer of similar diamond are adopted in 61-281030 and 1-301864 suggestion.Japan postpones the material that a kind of glass coating is adopted in publication No.64-83529 suggestion.Equally, the open No.2-31012 of Japanese Patent proposes a kind of method, and it is to form the thick carbon film layer of one deck 5-500nm on lens or forming mould.

Regrettably, above-mentioned its shortcoming of 13Cr Ma Shi steel is, the easy oxidation of steel, and the Fe in the steel diffuses in the glass, at high temperature forms the glass of band look.Usually, need to consider SiC and Si ₃N ₄Be not easy oxidation.Yet at high temperature, these materials meeting oxidations are subjected to melting and form SiO from the teeth outwards at glass ₂Material with the rare metal coating is not easy fusing, yet because this coating is very soft, so this material is easy to damage and deformation.

Usually, adopt class diamond carbon film layer, the a-C:H rete, or a kind of forming mould of hard carbon rete can improve the stripping feature between mould and the glass, and itself and glass are not melted.Yet when using the soft glass material, the demoulding causes the cracking of glass easily.So, require further to improve demolding performace.The diamond rete that one deck is thin has high hardness and high thermostability.And the demolding performace between this its mould of diamond-like carbon rete and the glass is not as good as above-mentioned diamond-like carbon rete, a-C:H rete and hard carbon rete, promptly so-called decolorizing carbon rete.So, the demolding performace of rete is also needed to improve.

In addition, in the embodiment described in the Japanese Patent No.2-31012, adopt vacuum deposition to form the carbon film layer.Yet, this carbon film layer usually to base lining and the object when being shaped a kind of weak sticking power is arranged.That is, rete has problems aspect wearing quality.

The present invention has considered said circumstances, and its objective is provides a kind of optical element forming mould, and it and glass are not fused, and have high rigidity, high surface smoothness and high mold durability, and the method for making this mould.

In order to address the above problem and obtain this purpose, first aspect of forming die for optical element of the present invention it is characterized in that by following structures be provided with characterize.

That is, this forming die for optical element is a kind ofly to utilize compression moulding to manufacture the forming die for optical element that glass optical component is used, and the TaN thin film layer that wherein includes elemental lithium or lithium compound is formed at least one module surface as a release layer.

According to second aspect, forming die for optical element of the present invention is characterized in that having following configuration.

That is, this forming die for optical element is a kind of forming die for optical element that utilizes compression moulding to manufacture glass optical component.Wherein, the titanium nitride TiN thin film layer that contains elemental lithium or lithium compound is formed at least one module surface as release layer.

According to the 3rd aspect, forming die for optical element of the present invention is characterized by following configuration.

That is, this forming die for optical element is a kind of forming die for optical element that utilizes compression moulding to manufacture glass optical component.Wherein, the ZrN thin film layer that contains elemental lithium or lithium compound is formed at least one module surface as release layer.

According to the 4th aspect, forming die for optical element of the present invention is characterized by following configuration.

That is, this forming die for optical element is a kind of forming die for optical element that utilizes compression moulding to manufacture glass optical component.Wherein, the TiC thin film layer that contains elemental lithium or lithium compound is formed at least one module surface as release layer.

According to the 5th aspect, forming die for optical element of the present invention is characterized by following configuration.

That is, this forming die for optical element is a kind of forming die for optical element that utilizes compression moulding to manufacture glass optical component.Wherein, the TiCN thin film layer that contains elemental lithium or lithium compound is formed at least one module surface as release layer.

According to the 6th aspect, forming die for optical element of the present invention is characterized by following configuration.

That is, this forming die for optical element is a kind of forming die for optical element that utilizes compression moulding to manufacture glass optical component.Wherein, the MoC thin film layer that contains elemental lithium or lithium compound is formed at least one module surface as release layer.

According to the 7th aspect, forming die for optical element of the present invention is characterized by following configuration.

That is, this forming die for optical element is a kind of forming die for optical element that utilizes compression moulding to manufacture glass optical component.Wherein, the SiC thin film layer that contains elemental lithium or lithium compound is formed at least one module surface as release layer.

According to the 8th aspect, forming die for optical element of the present invention is characterized by following configuration.

That is, this forming die for optical element is a kind of forming die for optical element that utilizes compression moulding to manufacture glass optical component.Wherein, the SiN thin film layer that contains elemental lithium or lithium compound is formed at least one module surface as release layer.

According to the 9th aspect, forming die for optical element of the present invention is characterized by following configuration.

That is, this forming die for optical element is a kind of forming die for optical element that utilizes compression moulding to manufacture glass optical component.Wherein, the CrC thin film layer that contains elemental lithium or lithium compound is formed at least one module surface as release layer.

Equally, characterize by following proposal according to the relevant method of manufacturing forming die for optical element of the present invention of first aspect.

Promptly, utilize compression moulding to manufacture in the forming die for optical element making method of glass optical component, utilizing the source metal material that contains elemental lithium or lithium compound to make the TaN thin film layer that comprises elemental lithium or lithium compound be formed at least one molded surface of forming mould as release layer by the ion plating film method.

According to second aspect, the method for manufacturing forming die for optical element of the present invention is characterized by following proposal.

Promptly, utilize compression moulding to manufacture in the forming die for optical element making method of glass optical component, utilizing the source metal material that contains elemental lithium or lithium compound that the TiN thin film layer that comprises elemental lithium or lithium compound is formed at least one molded surface of forming mould as release layer.

According to the third aspect, the method for manufacturing forming die for optical element of the present invention is characterized by following proposal.

Promptly, utilize compression moulding to manufacture in the forming die for optical element making method of glass optical component, utilizing the source metal material that contains elemental lithium or lithium compound that the ZrN thin film layer that comprises elemental lithium or lithium compound is formed at least one molded surface of forming mould as release layer.

According to fourth aspect, the method that the present invention manufactures forming die for optical element is characterized by following proposal.

Promptly, utilize compression moulding to manufacture in the forming die for optical element making method of glass optical component, utilizing the source metal material that contains elemental lithium or lithium compound that the TiC thin film layer that comprises elemental lithium or lithium compound is formed at least one molded surface of forming mould as release layer.

According to the 5th aspect, the method that the present invention manufactures forming die for optical element is characterized by following proposal.

Promptly, utilize compression moulding to manufacture in the forming die for optical element making method of glass optical component, utilizing the source metal material that contains elemental lithium or lithium compound that the TiCN thin film layer that comprises elemental lithium or lithium compound is formed at least one molded surface of forming mould as release layer.

According to the 6th aspect, the method that the present invention manufactures forming die for optical element is characterized by following proposal.

Promptly, utilize compression moulding to manufacture in the forming die for optical element making method of glass optical component, utilizing the source metal material that contains elemental lithium or lithium compound that the MoC thin film layer that comprises elemental lithium or lithium compound is formed at least one molded surface of forming mould as release layer.

According to the 7th aspect, the method that the present invention manufactures forming die for optical element is characterized by following proposal.

Promptly, utilize compression moulding to manufacture in the forming die for optical element making method of glass optical component, utilizing the source metal material that contains elemental lithium or lithium compound that the SiC thin film layer that comprises elemental lithium or lithium compound is formed at least one molded surface of forming mould as release layer.

According to eight aspect, the method that the present invention manufactures forming die for optical element is characterized by following proposal.

Promptly, utilize compression moulding to manufacture in the forming die for optical element making method of glass optical component, utilizing the source metal material that contains elemental lithium or lithium compound that the SiN thin film layer that comprises elemental lithium or lithium compound is formed at least one molded surface of forming mould as release layer.

According to the 9th aspect, the method that the present invention manufactures forming die for optical element is characterized by following proposal.

Promptly, utilize compression moulding to manufacture in the forming die for optical element making method of glass optical component, utilizing the source metal material that contains elemental lithium or lithium compound that the CrC thin film layer that comprises elemental lithium or lithium compound is formed at least one molded surface of forming mould as release layer.

According to the tenth aspect, the method that the present invention manufactures forming die for optical element is characterized by following proposal.

According to the tenth one side, the method that the present invention manufactures forming die for optical element is characterized by following proposal.

According to the 12 aspect, the method that the present invention manufactures forming die for optical element is characterized by following proposal.

Promptly, utilize compression moulding to manufacture in the forming die for optical element making method of glass optical component, utilizing the source metal material that contains elemental lithium or lithium compound that the TaN thin film layer that comprises elemental lithium or lithium compound is formed at least one molded surface of forming mould as release layer.

According to the 13 aspect, the method that the present invention manufactures forming die for optical element is characterized by following proposal.

According to the 14 aspect, the method that the present invention manufactures forming die for optical element is characterized by following proposal.

According to the 15 aspect, the method that the present invention manufactures forming die for optical element is characterized by following proposal.

According to the 16 aspect, the method that the present invention manufactures forming die for optical element is characterized by following proposal.

According to the 17 aspect, the method that the present invention manufactures forming die for optical element is characterized by following proposal.

According to the tenth eight aspect, the method that the present invention manufactures forming die for optical element is characterized by following proposal.

Promptly, a kind of method of manufacturing forming die for optical element that on molded surface, comprises at least one class basic metal release layer, wherein release layer is by a kind of sputtering method, promptly use the sputtering method of two or more targets, one of them target comprises a kind of basic metal, at least another target is by forming a kind of metallic carbide, a kind of metal nitride, or a kind of target of metal nitrogen carbon compound forms.

According to the 19 aspect, the method that the present invention manufactures forming die for optical element is characterized by following proposal.

Promptly, a kind of method of manufacturing forming die for optical element that on molded surface, comprises at least one class basic metal release layer, wherein release layer is formed by a kind of sputtering method, promptly this sputtering method utilizes two or more targets, one of them target comprises a kind of basic metal, at least another target is to be used to form metallic carbide, metal nitride, or metal nitrogen carbon compound, with a kind of basic metal and metallic carbide, the mixolimnion utilization of metal nitride or metal nitrogen carbon compound sputter simultaneously contains alkali-metal target and is used to form metallic carbide, and it is in 100mm or the scope more than the 100mm apart from the optical element forming surface at least that the target of metal nitride or metal nitrogen carbon compound is formed on.

The present inventor has obtained above-mentioned invention by following research.That is, in considering all problems that traditional forming die for optical element exists, the present inventor has carried out comprehensive experiment to the additive influence as the processability relation of the release layer of the upper layer of molded surface.Thus, the present inventor just might illustrate basic metal, and especially lithium is to the influence of processability.

The surface of traditional forming mould, any metallic carbide, the thin sintering rete of metal nitride and metal nitrogen carbon compound has great sticking power to glass, so there is the problem of demolding performace aspect.Therefore, for soft glass, the optical element of big lens diameter and the optical element of small curvature radius carry out when molded, and glass can ftracture and be attached to mould.To this, the present invention makes many researchs, obtains demolding performace preferably in the release layer by different elements is added to.Thus, the present inventor finds, when elemental lithium or lithium compound adding release layer, will the adhewsive action between mould and the glass be descended widely.

That is, although elemental lithium can be included in the glass of numerous species, this element has very high activity.Usually, never be proposed in and form the rete that comprises this element on the surface of mould, also do not use this rete as release layer.Yet above-mentioned extensive studies disclosed by the present inventor does, existed the elemental lithium of trace or its compound will help to improve demolding performace between mould and the glass on the surface of mould.Though its reason is also very unclear so far, but deducibility goes out elemental lithium and its compound, oxide compound for example, the characteristic that has low fusing point and gasify easily when the glass molding temperature is so this element or compound have the function as release layer (being a kind of gas-bearing formation in this case) in the interface between glass and mould.

So the present invention realizes forming die for optical element based on this, this mould not with glass melting, have high hardness, high surface flatness and high molded wearing quality.

Equally, on manufacturing molded surface, have in the forming die for optical element method of the alkali-metal release layer that includes a type at least, this release layer is formed by sputtering method, this sputtering method uses two or more targets, at least one target contains basic metal, at least remaining target is one and is used to form metallic carbide, the target of metal nitride or metal nitrogen carbide.This method is used to form a kind of forming die for optical element, it not with glass melting, have high hardness, high surface smoothness and high mold durability.

In addition, in the present invention, including at least a alkali-metal release layer is to utilize sputtering method to be formed on the molded surface, this sputtering method utilizes two or more targets, at least one target contains basic metal, at least remaining target is to be used to form metallic carbide, the target of metal nitride or metal nitrogen carbide.Thus, can controllably add the basic metal height to metallic carbide, in metal nitride or the metal nitrogen carbide.

Purpose except that above-mentioned discussion and advantage can be learnt that for a person skilled in the art specification sheets is still needed referring to accompanying drawing by the description of following preferred embodiment, and accompanying drawing is the part of specification sheets, and it is of the present invention giving an example.Yet such example is not to cover all embodiment of the present invention, so also need referring to claim, it is used for determining scope of invention after being positioned at specification sheets.

Figure 1A and 1B represent the schematic cross-section of forming die for optical element of the present invention;

Fig. 2 represents to adopt the ionization method of coating to form the device synoptic diagram of release layer by first embodiment;

Fig. 3 represents to adopt sputtering method to form the device synoptic diagram of release layer by first embodiment;

Fig. 4 represents to adopt the lens shaped device sectional view by forming die for optical element of the present invention;

Fig. 5 represents the table as a result to example 5 and comparative example 1 to example 4 of example 2 among first embodiment;

Fig. 6 represents that example 6 is to the table as a result of example 10 and comparative example 5 and example 6 among first embodiment;

Fig. 7 represents that example 11 is to the table as a result of example 16 and comparative example 7 and example 8 among first embodiment;

Fig. 8 represents that example 19 is to the table as a result of example 21 among first embodiment;

Fig. 9 represents that example 22 is to the table as a result of example 24 among first embodiment;

Figure 10 represents to adopt the release layer of the sputtering method of second embodiment to form schematic representation of apparatus;

Figure 11 represents the table as a result to example 5 and comparative example 1 to example 4 of example 2 among second embodiment;

Figure 12 represents that example 6 is to the table as a result of example 11 and comparative example 5 and example 6 among second embodiment;

Figure 13 represents that example 12 is to the table as a result of example 15 and comparative example 7 and example 8 among first embodiment;

Figure 14 represents that example 16 is to the table as a result of example 20 and comparative example 9 and example 10 among second embodiment.

First embodiment

To manufacture the method for forming die for optical element referring to description of drawings the present invention below.Figure 1A and 1B are the schematic sections of forming mould.In Figure 1A and 1B, reference numerals 1 expression mold base metal, 2 any metallic carbide of serving as reasons, metal nitride and the made thin film layer of metal nitrogen carbide, contain one or more lithiums in these metal objects, potassium and sodium element, perhaps one or more compounds of these elements.Referring to Figure 1B, middle layer 3 is formed on mold base metal 1 and metallic carbide, between the thin film layer 2 of metal nitride or metal nitrogen carbide.

Though this embodiment represents a kind of concavees lens forming mould, the present invention is not limited to the concavees lens forming mould.That is, the present invention can be applicable to the convex lens forming mould equally, spherical lens forming mould, forming die for optical element such as cylindrical lens forming mould.

In the present invention, contain one or more lithiums, potassium and sodium element, perhaps the release layer of the compound of one or more these elements is used as the thin film layer on the molded surface of forming mould, this release layer adopts and includes one or more lithiums, potassium and sodium element, perhaps the compound of these elements perhaps adopts and is selected from a kind of metallic carbide as source metal, the material of metal nitride and metal nitrogen carbide is formed by ionization method of coating or sputtering method.Consequently, at least one molded surface of mould, form arbitrary layer and include one or more lithiums, potassium and sodium element, the perhaps thin film layer of the compound of one or more these elements.

Fig. 2 is illustrated in rete used in the ionization method of coating and forms the device synoptic diagram.In Fig. 2, numeral 21 expression vacuum vessels; 22 expressions are connected to oil diffusion pump, the venting port of rotor pump and vacuum pump (all not shown); 23 expression air feed ports; 24 expressions are connected to gas bomb, the airflow rate controller of pressure-regulator and valve (not shown).

Numeral 25 expression radio frequency power supplys; 26 expression matching boxs; 27 expression RF coils; 28 expression base lining seats; 29 expression base linings.By DC power supply 210 negative direct-current biasing is added to base lining and base lining seat, 211 expression electron sources; The power supply of 212 expression electron sources 211.Adopt the electron source 211 ejected electron bundles can hot melt and gasification source metal, or metallic carbide, metal nitride and metal nitrogen carbide material (evaporation source hereinafter referred to as).

The step of above-mentioned ionization method of coating is as follows:

(1) contain one of carbon and nitrogen to the major general, perhaps both gas adds vacuum vessel.

(2) by electron beam evaporation source 213 is melted and evaporation.

(3) will contain a kind of in carbon and the nitrogen, or both gas and evaporation source material become a kind of plasma body, become ion then under radio frequency conditions.

(4) by the base lining is applied negative bias ionizing radiation to base is served as a contrast.

(5) contain a kind of in carbon and the nitrogen, or both gas and evaporation source material allow in plasma body, or on the surface of base lining, interact.

(6) on base lining surface, form any metallic carbide, the thin film layer of metal nitride and metal nitrogen carbide.

Ionization method of coating of the present invention is not limited to above-mentioned device and system fully.For example, in this method, also can adopt electric energy to come hot melt and gasification evaporation source, perhaps utilize direct current arc to discharge and melt and the evaporation source that gasifies.DC discharge also can be used for forming the plasma body of the metal of a kind of gas and gasification.In addition, can adopt the method that applies radio frequency to come to base lining biasing.

The rete that Fig. 3 represents to be used in the sputtering method forms schematic representation of apparatus.In Fig. 3, numeral 31 expression vacuum vessels; 32 expressions are connected to oil diffusion pump, the venting port of rotor pump and vacuum pump (all not shown); 33 expression base lining seats; 34 expression base linings; 35 expressions are connected to gas bomb, the air feed port of pressure-regulator and valve (all not shown).

A kind of metallic carbide of selecting for use of numeral 36 expressions, metal nitride and metal nitrogen carbide material (below be called target material); 37 expression RF power supplys; 38 expression matching boxs.

When adopting this sputtering method in said apparatus, the molded surface of forming mould is formed by following step.

(1) contain one of carbon and nitrogen to the major general, perhaps both gas infeeds vacuum vessel.

(2) by target material is added radio frequency, will contain one of carbon and nitrogen at least, or both gas and evaporation source material are transformed into plasma body, become ion then.

(3) target material is subjected to sputter.

(4) in plasma body, or at lip-deep one of carbon and the nitrogen of containing of base lining, or both gas and target material can interact.

(5) on base lining surface, form any metallic carbide, the thin film layer of metal nitride and metal nitrogen carbide.

Sputtering method of the present invention is not limited to above-mentioned device and system fully.For example, also can use a kind of device of dc energy source or system to come the lieu of radio-frequency energy.Also can use magnetron sputtering method, wherein one magnet is set, perhaps adopt the subtend sputtering method of the mutual subtend of target material near target material.

In above-mentioned ionization method of coating and sputtering method, form any metallic carbide, the thin film layer of metal nitride and metal nitrogen carbide needs following method.

(1) utilize fusing or sputter to make base serve as a contrast lip-deep a kind of metallic carbide that are selected from, the metallic substance source of metal nitride and metal nitrogen carbide obtains gasification.

(2) make and contain one of carbon and nitrogen at least, or both gas becomes a kind of plasma body.

(3) in plasma body, perhaps at lip-deep one of carbon and the nitrogen of containing of base lining, or both gas, the gas of evaporation source or target can interact.

(4) on base lining surface, form any metallic carbide, the thin film layer of metal nitride and metal nitrogen carbide.

A kind of metallic carbide can pass through carbonaceous gas, for example, hydrocarbon gas, as methane, ethane, ethene, or acetylene, carbon monoxide, or halo carbon are added to rete and form in the gas, and make gas and metal function.A kind of metal nitride can be with for example, nitrogen, and ammonia, or nitrogenous gas such as halo nitrogen is added to rete and forms in the gas, and gas and metal function are formed.A kind of metal nitrogen carbide can form in the gas by carbonaceous gas and nitrogenous gas being added to rete, and these gases and metal function are formed.

In this generation type, can be suitably with hydrogenous gas, or a kind of rare gas element (as, helium, argon, neon) be added to rete and form in the gas.Especially, in sputtering method, need to add the rare gas element with obvious sputter effect, for example argon gas.

In the present invention, when thin film layer is by the ionization method of coating, utilize any metallic carbide, when metal nitride and metal nitrogen carbide form, can be by being selected from one or more in lithium, potassium and the sodium element, perhaps one or more compounds of these elements are added into and are selected from metallic carbide, in the source metal or metallic substance of metal nitride and metal nitrogen carbide, with lithium, one or more elements in potassium and the sodium are added to any metallic carbide, in nitride and the formed thin film layer of metal nitrogen carbide.

In the present invention, at thin film layer is to utilize any metallic carbide, metal nitride and metal nitrogen carbide, when forming by sputtering method, can be by being selected from lithium, one or more elements in potassium and the sodium element, perhaps one or more compounds of these elements are added to target material, perhaps by containing one or more lithiums, the element of potassium and sodium, or the small-particle of one or more compounds of these elements is placed on the target material, with lithium, one or more elements of potassium and sodium are added to any metallic carbide, in metal nitride and the formed thin film layer of metal nitrogen carbide.

At any metallic carbide, the lithium in the thin film layer of metal nitride and metal nitrogen carbide, the content of one or more elements of potassium and sodium are 0.05-5 atom %, select 0.1-2 atom % for use, especially select 0.5-1 atom % for use.Described here content (atom %) is meant and only contains a kind of lithium in thin film layer, a kind of content of element when potassium and sodium element, and when comprising two kinds or two or more element the total content of these elements.

If this content is less than 0.05 atom %, one or more lithiums then, the interpolation of potassium and sodium element does not tell on.If content surpasses 5 atom %, any metallic carbide then, the thin film layer of metal nitride and metal nitrogen carbide can make the debase of rete, although be good with respect to its demolding performace.

Lithium, potassium and sodium all have good demolding performace for glass.Especially, lithium has good demolding performace and high molded wearing quality.

When molded major diameter lens or meniscus lens, the effect that adds lithium is very significant.When molded major diameter lens (for example 30 φ or more than), in mould a kind of big stress can appear usually, obviously this will cause demoulding unfavorable.Equally, when molded meniscus lens (especially concave surface meniscus lens), stress can occur in the outer rim of lens, it can make its outer peripheral edges split, and perhaps is unfavorable for release layer.On the contrary, according to forming die for optical element of the present invention, have any metallic carbide that contain lithium, metal nitride, with the thin film layer of metal nitrogen carbide as release layer, this mould has good demolding performace, and suppresses the deterioration of release layer and the cracking of glass.This forming die for optical element is best as the mould of molded major diameter lens or meniscus lens.

Add one or more lithiums, the example of the method for potassium and sodium element is, a kind of with lithium, potassium and sodium element are added to the method for evaporation source or target material, with a kind of with the form of these elements with different compounds, for example oxide compound, halogenide, carbonate, vitriol, the form of nitrate is added to the method for evaporation source or target material.Also can be with lithium, potassium and sodium element, or the compound of these elements adopts evaporation or sputter that the mode of element or compound gasification is introduced in the film formation atmosphere.Thus, these elements can be added to any metallic carbide, in the thin film layer of the shaping of metal nitride and metal nitrogen carbide.

Yet, need point out, should be careful, owing to be added to one or more lithiums in evaporation source or the target material, the ratio of potassium and sodium element is to be not equal to be included in any metallic carbide in many cases, one or more lithiums in the form film layer of metal nitride and metal nitrogen carbide, the ratio of potassium and sodium element.This is because the vapour pressure of evaporation source or target material or sputter rate are different from every kind of lithium, potassium and sodium element, or the vapour pressure of the compound of these elements and sputter rate.

So, in the present invention, one or more lithiums, potassium and sodium element are at any metallic carbide, addition in metal nitride and the metal nitrogen carbide is different from one or more lithiums, potassium and the sodium element addition in evaporation source or target material, and they must be set in the above-mentioned scope.

According to the present invention, any metallic carbide, metal nitride, the thin film layer of metal nitrogen carbide can be according to the kind of glass, and molding temperature is selected different thin film layers for use with molded atmosphere different.Yet, when considering thickness and heat-resistant quality, preferably use the carbide of 4A in the periodic table of elements, 5A, 6A group element and silicon, nitride and nitrogen carbide.In the present embodiment, the 4A group element of periodictable is Ti, Zr and Hr, and the 5A group element of periodictable is V, Nb and Ta, and the 6A group element of periodictable is Cr, Mo and W.

Usually, silicon is not classified as metal.Yet, will be among the present invention the carbide of silicon, nitride and nitrogen carbide are called a kind of metallic carbide, metal nitride and metal nitrogen carbide, this is that a kind of generalized is represented.

The carbide of periodictable 4A, 5A and 6A group element and silicon, nitride and nitrogen carbide have high hardness (1000 or above Vickers thickness, be typically 2000 or more than), and deformation is little when molded.In addition, the carbide of these elements, nitride and nitrogen carbide have high fusing point (1500 ℃ or more than, representational be 2000 ℃ or more than), when high temperature, have high stability thus.So these compounds and glass effect are little, and has high molded weather resistance.

As mentioned above, a kind of release layer of the optical element module with good demoulding properties and high molded weather resistance can be by with one or more lithiums, potassium and sodium element are added to any carbide of 4A, 5A, 6A group element and the silicon of periodictable, obtain in the thin film layer of nitride or nitrogen carbide.; when the element that one or more is selected from lithium, potassium and sodium is added in the thin film layer that is not any metal or alloy in the scope of the invention; its demolding performace just not as belong to the 4A at periodictable, 5A in the scope of the invention, 6A group element any; or the carbide of silicon, obtained raising under the sort of situation of the thin film layer of nitride and nitrogen carbide.Though its reason be it be unclear that, obviously the alloy of formed lithium, potassium and sodium will make rete stable in thin metal film or thin alloy film, thereby this rete will not play release layer.Equally, the thin film layer of metal or alloy has low fusing point usually, and at high temperature unstable.In addition, a kind of like this thin film layer is easy to work with glass, and distortion, and wearing and tearing and damage are so the forming stability of film is low.

One or more lithiums, the element of potassium and sodium do not need to be added to any metallic carbide, in the whole thin film layer of metal nitride and metal nitrogen carbide.That is, only these elements need be added to any metallic carbide, the surface of the adjacent films layer of metal nitride and metal nitrogen carbide.Any metallic carbide, contiguous place, the surface of the thin film layer of metal nitride and metal nitrogen carbide is meant the zone that is about the hundreds of millimicron at a distance of the film surface.Especially, in distance film surface 100mm or unlikely 100mm scope, one or more lithiums, the big young pathbreaker of the concentration of potassium and sodium element has great contribution to molded characteristic.So, forming any metallic carbide, the starting stage of the thin film layer of metal nitride and metal nitrogen carbide, need to reduce one or more lithiums, the add-on of potassium and sodium element, perhaps any does not all add.The final stage that forms at rete only, promptly layer thickness is selected from lithium to one or more in hundreds of millimicron or following zone, and the element of potassium and sodium is set up the concentration (0.05-5 atom %) by the present invention limited.

The example that is used for base lining of the present invention is that oxide compound is the pottery of base material, for example alumina-ceramic and zirconia ceramics; Carbide and nitride are the pottery of base material, silicon carbide for example, silicon nitride, titanium carbide, titanium oxide, and wolfram varbide; The Wimet of WC-base material; Metal, for example molybdenum, tungsten and tantalum metal.

In the present embodiment, can form device, perhaps need molded lens shape to come to determine suitably the shape of base lining according to rete.For example, when the need moulded lens, make molded surface become curved surface shaped according to the radius-of-curvature of lens diameter.Can utilize gas-phase synthesizing method on curved surface, to form any metallic carbide, the thin film layer of metal nitride and metal nitrogen carbide.

Example

The present invention will be described in detail by following example.(example 1)

In the present example, the release layer of being made by tantalum nitride is by the embodiment shown in Fig. 2, promptly utilizes the method for ionization coating to form.Used mould base metal is to use the SiC sintered article is processed into predetermined shape makes, and forms one deck polycrystalline Si C rete with the CVD method, and the polished die control surface is the minute surface of Rmax=0.04 μ m again.

This forming mould is cleaned well, put into ion plating film device shown in Figure 2 again.Tantalum powder (100 order) is sneaked into the lithium chloride (LiCl) of 0.1 atom % in the lithium powder as source metal.Vacuum vessel 21 is evacuated down to after the predetermined vacuum tightness,, supplies with nitrogen and argon gas with the flow velocity of per minute 20ml from air feed port 23.

Pressure is 2.7 * 10 ^-2Crust (Pa).Utilize RF power supply 25 (frequency is 13.56MHz) to apply the radio frequency output of 500W, form plasma body at nearly RF coil 27 places.In addition, use the bias voltage of DC power supply 210 general-150V to be added to base lining 29 and base lining seat 28.Equally, utilize electron source 211 that the tantalum source is melted.By above-mentioned operation, on the molded surface of mould base metal, form the thick titanium nitride film of one deck 1.5 μ m.Utilize secondary ion mass spectrometry (SIMS) figure (SIMS) beasurement base to be same as the formed analytical sample of integrated condition of above-mentioned thin tantalum nitride rete.So the lithium content that records the surface (in the zone of the about 20nm in surface) at the contiguous tantalum nitride rete that approaches is about 1.0 atom %.

To introduce the result that the forming die for optical element that uses this example carries out pressed glass lens below.In glass lens pressing unit shown in Figure 4, numeral 41 expression vacuum vessels; The patrix of 42 expression molding of optical elements; 43 expression bed dies; 44 expressions are to the patrix pressing means of patrix pressurization usefulness; The round axle of 45 expressions; 46 expression mould strut members; 47 expression heating members; 48 expressions promote the push rod that bed die is used; The cylinder that 49 expression operation push rods are used; 410 expression backing pumps; 411,412 and 413 expression valves; 414 expression rare gas element supply valves; 415 expression valves; 416 expression gas leak valve; 417 expression valves; 418 expression temperature sensors.

The molded glass of desire is a kind of flint optical glass SF14 (softening temperature Sp=586 ℃, transition point Tg=485 ℃), and coming molded diameter by this glass is 30mm, with thickness than the convex lens that are 4.Molded condition is in nitrogen atmosphere, and pressed temperature is 588 ℃.Carrying out when molded and shaped, the demolding performace between forming mould and the molded optical element is good.Utilize the optical illumination forming mould of spot light lamp, and the surface seen look, check the surface of mould with this.If rete peels off or ftractures, glass melting perhaps appears, then can see at relative section having trace note clearly with above-mentioned inspection method.Yet when the forming die for optical element that this example is formed was observed with this inspection method, it was very good to observe the minute surface performance, and not because the peeling off or ftractureing of rete, perhaps the fusing of glass and the trace that forms is remembered.Then can be sure of, use scanning electronic microscope again, 500 * surface of above-mentioned forming die for optical element is observed to 5000 * multiplying power.Thus, can find had not both had peeling off of rete, did not have the cracking of rete yet, and did not have glass to be melted yet.The surperficial feelings of equally, molded glass lens can also be similar to the inspection of direct-view.In a word, on the surface of lens, do not observe cloud, trace note and small roughness.

A kind of forming die for optical element, except the condition of in tantalum nitride, not adding the lithium other with above-mentioned identical.By last, though being same as above-mentioned glass material, utilization carries out the molded and shaped of glass with identical shape, the film mould power between mould and the glass is very strong.So, can be observed the cracking of glass and to the partial melting of mould.(example 2-5, comparative example are 1-4)

Example 2-5 will be described below with the example 1-4 that compares.In these examples and the example of comparing, various element is added in the titanium nitride film, and their effect is made an appraisal.Thin titanium nitride film is synthetic by the ion plating film method.With mould base metal, a kind of Wimet of WC base material is processed into predetermined shape.Last forming mould is cleaned well and is placed in the device shown in Figure 2, carry out the synthetic of titanium nitride again.Titanium valve (100 order) is as source metal, and each different interpolation of 0.2 atom % adds.Other synthesis condition is, each supplies with nitrogen and argon gas with the flow velocity of per minute 25ml, and bias voltage is-120V, and RF is output as 400W, and air pressure is 3.3 * 10 ^-2Crust.With this understanding, form the titanium nitride film that thickness is about 1.2 μ m.

In turn, use this forming die for optical element to carry out the type of making of glass lens.Mold pressing is (not shown) of adopting the continuous molding device to implement, and the opticglass SF14 of flint base material (softening temperature Sp=586 ℃, transition temperature Tg=485 ℃) is as the molded glass material of desire.Under nitrogen atmosphere, when being 588 ℃, pressed temperature can carry out 5000 compression moulding.Lens shape is similar to the shape shown in the example 1.Various results are illustrated among Fig. 5.

In Fig. 5, by the concentration that measures various elements in titanium nitride film to the evaluation and test sample, these samples are to utilize SIMS to obtain respectively under identical synthesis condition at same mould.

The moulded product surface property is to adopt the lens that the rayed of spot light lamp is molded, and sees and look its surface property (lip-deep cloud and mist, trace note and trickle roughness) and assess.Whether evaluating standard is a foundation, compare molded lens with so-called " MIN sample " and can determine as this foundation that product uses.The condition that described " MIN sample " needs to satisfy is; surfaceness or surface deformation line (with the difference of desirable lens shape) are about a Newton's rings; maximum surface irregularity (P-V value) is about 30nm; average surface roughness (RMS) is about 5nm; big vestige number to about 10 μ m is 2 in whole lens, and these vestiges are not close together mutually.The surface property moulded product poorer than " bottom line sample " can not use as product.In evaluation criteria, X presentation surface performance is poorer than " bottom line sample ", and this moulded product can not be as product.△ presentation surface performance is same level for " bottom line product " compared, and perhaps can be analogous to the surface property of " bottom line product " by simply wiping clean.Zero presentation surface performance is better than " bottom line sample ".◎ presentation surface performance is best, does not have phenomenon appearance such as cloud and mist.Its assessment of module weather resistance is to be identical or to be better than according to the number of the molded number of the regulation of product than common molded " bottom line sample ".X represents because the fusing of glass or cracking can not make the product number of regulation obtain molded.△ represent can molded similar regulation the product number.The number of zero expression moulded product can surpass 1.5 times of specified number or amounts or more than.◎ represent moulded product outnumber 2 times of defined amount or more than.

In example 2 to 5, one or more lithiums, potassium and sodium element join in the titanium nitride film, can obtain satisfied moulded product surface property and molded weather resistance as forming die for optical element.By contrast, in example 1 to 4, the surface property of moulded product and molded weather resistance reduce, this be because the element that adds outside above-mentioned scope.Especially in the example of comparing 1 to 3, the sticking power that forms between mould and the glass is high to the demolding performace decline that makes between mould and the glass, and makes some molded glass products crackings.In addition, because glass cracking and being adhered on the mould, so will in molded process of the test, clean to mould.Equally, in the example of comparing 4, the impaired significantly and peeling of titanium nitride film.Thus, the surface property of molded glass reduces, and this will make molded glass be not suitable for actual use.

In above-mentioned the present invention, in titanium nitride film, add one or more lithiums, potassium and sodium element, just can obtain satisfied moulded product surface property and molded weather resistance by the forming die for optical element of gained.(routine 6-10, phase ratio 5 and 6)

Example 6-10 and ratio 6 mutually and will be by describing below.In these examples and comparative example, will the concentration of element that add in the titanium nitride thin rete be made assessment.Adopt the ion plating film method to form titanium nitride film by being analogous to the step described in the example 2.Equally, at first the die holder base metal is processed into predetermined shape.The forming mould that processes cleaning, and be placed in as shown in Figure 2 the device, form one deck titanium nitride thin rete.In the rete forming process, change the amount of the lithium that is added to titanium nitride to the amount of the lithium nitride of metal titanium material.Other synthesis condition is that the source flow rate of gas is: nitrogen 20ml/min, argon gas 30ml/min, bias voltage be-100V, and RF output is 400W, and pressure is 3.5 * 10 ^-2Pa.Thus, form the titanium nitride film that thicknesses of layers is about 1nm.

Then, utilize this forming die for optical element to come pressed glass lens.This molded be to adopt a kind of apparatus for continous formation to carry out, the opticglass SF14 of flint base-material (softening temperature Sp=586 ℃, transition point Tg=485 ℃) is used as the molded glass of desire.In nitrogen atmosphere, the compacting module can use 5000 times when 588 ℃ of press temperatures.It is described that the shape of lens is similar to example 1, consequently shown in Figure 6.

In Fig. 6, by the evaluation and test of each sample being obtained the lithium concentration value in the titanium nitride, these samples are to adopt the SIMS method to form respectively under identical forming mould synthesis condition.

In example 6 10, as the molded article surface performance of the satisfaction of forming die for optical element and module weather resistance its to obtain to be 0.05-5 atom % by the concentration of setting elemental lithium, on the contrary, in comparative example 5 and 6, because elemental lithium concentration is not in above-mentioned scope, therefore molded surface property and molded weather resistance lower.In addition, in comparative example 5, the sticking power between mould and the glass is big, because the concentration of elemental lithium is low.So in molding process, the demolding performace between module and the glass descends, and has some molded glass products to ftracture.Also have, because glass cracking and being adhered on the mould, so just need clean module when testing carrying out module.Equally, in comparative example 6, elemental lithium concentration is high, so carrying out when molded, titanium nitride film is damaged, rete wearing and tearing and aliquation.Thus, the surface property of molded glass reduces, molded glass workpiece be not suitable for actual use.As mentioned above, be lower than 0.05 atom % when adding concentration of element, the demoulding performance between mould and the glass is not satisfied when molded.When adding concentration of element greater than 5 atom %, the film forming properties of thin titanium nitride film descends.This will cause the wearing and tearing or the aliquation of rete.

In foregoing invention, one or more elements that are selected from lithium, potassium and sodium are added in the release layer, the concentration of addition element is 0.05 to 5 atom %, can obtain satisfied molded article surface performance and module wearing quality as forming die for optical element.(routine 11-16, comparative example 7 and 8)

Routine 11-16 and comparative example 7 and 8 will be described below.In these examples and comparative example, form different film mould layers and to they test and appraisal.The following step identical with above-mentioned ion plating film method forms these release layers.Equally, at first the mold base metal is processed into predetermined shape.The mould that is processed is cleaned well and is placed in the device shown in Figure 2, form release layer (film).In film formation process, use different source metal, selected gas is as follows:

(1) when forming metal nitride, nitrogen is 20ml/min, and argon gas is: 20ml/min.

(2) when forming metallic carbide, methane is: 20ml/min, argon gas are: 20ml/min.

(3) when forming the metal nitrogen carbide, nitrogen is: 10ml/min, methane are: 10ml/min, argon gas are: 20ml/min.

And, with lithium chloride add source metal, lithium adds in the release layer.Other synthesis condition is, bias voltage-100V, and RF exports 400W, pressure 3.5 * 10 ^-2Pa, thicknesses of layers are about 1 μ m.

Then, carry out the compression moulding of glass lens with this forming die for optical element.This compression moulding is to utilize a successive molding device to carry out, and uses the glass of the opticglass SF14 (softening temperature Sp=586 ° some transition temperature Tg=485 ℃) of flint base-material as the desire compacting.In nitrogen atmosphere, under 588 ℃ of situations of press temperature, can carry out 5000 compression moulding.Lens shape is similar to shown in the example 1.The results are shown in shown in Figure 7.

In Fig. 7, by measuring the concentration that sample to be tested obtains lithium in the release layer, these samples under the synthesis condition identical with forming mould, form with SIMS respectively.Find that in all these samples, lithium concentration is 0.5-1.2 atom %.

In routine 11-16, utilize 4A in the periodictable, 5A and 6A to organize arbitrary group the element and the carbide of element silicon, the thin film layer of nitride and nitrogen carbide can obtain as optical element mold satisfied moulded product surface property and molded wearing quality.Otherwise, in comparative example 7 and 8,, the surface property of moulded piece and molded weather resistance are descended because the element that adds exceeds above-mentioned scope.

Especially in comparative example 7, because rete and glass have big functionality, so the clinging power between mould and the glass is strong.So the demolding performace when molded between mould and the glass descends, some molded glass product cracking.Also have because glass cracking and adhere to mould, so need be when molded test cleaning mold.

Equally, in comparative example 7 and 8, may be because the hardness of rete be low, so rete damages, when carrying out pressing mold, rete weares and teares and aliquation.So the surface property of molded glass goods descends, make this glasswork can not be practical.(example 17)

Example 17 is introduced below.In this embodiment, utilize sputtering method to form the release layer that one deck is made by thin chromium carbide.Use sputter equipment shown in Figure 3 to form this chromium carbide rete.In this embodiment, use the chromium of the Lithium Oxide 98min that contains 1 atom % as target.Simultaneously, will be processed into predetermined shape by the mold base that ceramic carbide is made, it will be put into sputter equipment shown in Figure 3, form one deck chromium carbide thin film layer.Formation condition is: airflow rate is methane: 20ml/min, and argon gas: 10ml/min, base lining temperature is a room temperature, RF output: 400W, pressure: 5 * 10 ^-1Pa.Under this condition, form the chromium carbide rete that thickness is about 800nm.

Measured with SIMS being same as under the synthesis condition of above-mentioned forming mould the sample to be tested that forms respectively.So the elemental lithium concentration that records in the chromium carbide is 2.1 atom %.

Molded durability test carries out with this mould.Utilize a successive device for molding to carry out moulded section, the glass of desiring mold pressing is crown optical glass SK12 (softening temperature Sp=672 ℃, transition point Tg=550 ℃).Molded diameter 35mm, diameter thickness is than the convex lens that are 4.Under nitrogen atmosphere, when 620 ℃ of press temperatures, carry out 5000 compression moulding.

As a result, in whole molding process, the demolding performace between mould and the molding of optical elements is good.Use the sem observation die surface after compacting, both do not found that the aliquation of rete is not found cracking yet, also do not have glass to be melted, this represents good die surface performance.Equally, molded glass lens has practical surface planarity.

A forming die for optical element is not added to all the other conditions the chromium carbide rete all with above-mentioned identical except there being lithium, and carries out the molded of glass with glass material same as described above with identical shape.Thus, the demoulding reactive force between mould and the glass is strong, the glass cracking, and part is fused on the mould.(example 18)

Example 18 is described below.In these row, thin silicon carbide film layer utilizes sputtering method to form one deck release layer.Utilize sputter equipment shown in Figure 3 to form this silicon carbide film layer.In this embodiment, silicon carbide is as target, boronation lithium (LiB ₂) small-particle be placed on the surface of target, thereby lithium is added in the carborundum films layer.

The mould metal base that is processed into certain shape by the ceramic carbide material is put into device shown in Figure 3, and forms one deck carborundum films layer.Formation condition is airflow rate: methane is 10ml/min, and argon gas is 30ml/min, and base lining temperature is 200 ℃, and RF output is 400W, and pressure is 5 * 10 ^-1Pa.Under this condition, on module surface, form the silicon carbide film layer that thickness is about 1.2 μ m.

To utilizing SIMS to measure being same as under the synthesis condition of above-mentioned forming mould the sample to be tested that forms respectively.So, record that the concentration of elemental lithium is about 2.1 atom % in silicon carbide film layer.

Carry out molded endurance test with this mould.This compression moulding is undertaken by a kind of apparatus for continous formation, and the molded glass of desire is crown optical glass SK12 (softening temperature Sp=672 ℃, transition point Tg=550 ℃).Molded convex lens diameter is 35mm, and diameter is 4 with the thickness ratio.In nitrogen atmosphere, when pressure and temp was 620 ℃, compression molding was carried out 5000 times.

As a result, in molding process, the demolding performace between mould and the molding of optical elements is good.To after molded with the surface of sem observation mould, do not observe the aliquation and the cracking of rete, do not have glass melting yet, this shows good die surface performance.Equally, molded glass lens has practical satisfied surfaceness.

A kind of forming die for optical element is by being same as above-mentioned condition, not adding in silicon carbide film layer the lithium, forming, and adopt glass material same as described above and shape to carry out the molded and shaped of glass.So the knockout press between mould and the glass is strong, so the glass cracking also partly is fused to mould.(routine 19-20)

In routine 19-20, form the release layer that makes with the titanium nitride thin rete by sputtering method.These titanium nitride films are to utilize sputter equipment shown in Figure 3 to form.In these examples, titanium is as sputtering target, and lithium particle as shown in Figure 8 is placed on the surface of target, so lithium is added in the titanium nitride thin rete.

To put into device shown in Figure 3 by the shaped mould metal base of ceramic carbide material, and form the titanium carbide thin film layer.Formation condition is airflow rate: nitrogen is 10ml/min, and argon gas is 15ml/min, and base lining temperature is 180 ℃, and RF output is 420W, and pressure is 4 * 10 ^-1Pa.Under this condition, about 1.5 μ m are thick for formed titanium carbide thin film layer.Utilization is being same as the sample to be tested that forms respectively under the synthesis condition of above-mentioned forming mould, adopts the lithium concentration in the SIMS measurement titanium nitride.Gained the results are shown in Figure 8.

Utilize this mould to carry out molded durability test.Utilize a continuous pressing machine to carry out this compression moulding, the glass of desire compacting is crown optical glass SK12 (softening temperature Sp=672 ℃, transition point Tg=550 ℃).Molded male bend moon lens diameter be 35mm.Under nitrogen atmosphere, when 620 ℃ of press temperatures, carry out 5000 compression moulding.

As shown in Figure 8, in pressing process, the demoulding performance between mould and the molding of optical elements is good.When after compacting, using the sem observation die surface, do not find the aliquation and the cracking of rete, do not have glass melting yet, show good die surface performance.Equally, molded glass lens have practical satisfied surfaceness.A kind of forming die for optical element is being similar to above-mentionedly, except not adding in titanium nitride the lithium, forms under the identical condition, and utilizes above-mentioned identical glass material and identical shape to carry out the glass compacting.As a result, the knockout press between mould and the glass increases, thus the glass cracking, and partial melting is in mould.(routine 22-24)

In routine 22-24, molded male bend moon glass lens (being equivalent to SF8).Utilize with routine 19-21 in identical sputtering method form release layer by the titanium nitride making.In routine 22-24, titanium is as target, and small-particle as shown in Figure 9 is placed on the surface of target, so alkali metal is added to the titanium nitride thin rete.

The mold base metal that becomes the sintered carbide of the WC-base-material of definite shape to manufacture by preprocessing is placed in the device shown in Figure 3, and forms titanium nitride film.Formation condition is that airflow rate is: nitrogen is 8ml/min, and argon gas is 13ml/min, and base lining temperature is 100 ℃, and RF output is 1000W, and pressure is 0.35Pa.Under this condition, formed silicon carbide film bed thickness is about 0.8 μ m.Utilize respectively by the sample to be tested that forms with the used identical synthesis condition of above-mentioned forming mould, with the alkali metal concn in the SIMS measurement rete, measured result is seen Fig. 9.

Utilize this forming mould, and a kind of continuous molding device carries out molded durability test.The molded glass of desire is SF8, and molded male bend moon lens diameter is 25mm.Molded and shaped condition is that employing nitrogen atmosphere and press temperature are 590 ℃.

As shown in Figure 9, the demolding performace between mould and the molded optical element is satisfied in practicality.Especially, use the titanium nitride film contain lithium during as release layer (example 22), the surface property of moulded product is good.During die surface after utilizing sem observation molded, do not find the fusing of the aliquation and the glass of mould layer, the good mould of this expression is represented performance.

A kind of forming die for optical element adopts and is analogous to above-mentioned condition, do not form except add the condition the alkali metal this point in titanium nitride film under, and the moulding of glass elements is to adopt glass material and shape same as described above to carry out.So the outer peripheral edge portion that is molded glass elements ftractures, segment glass is fused to mould.(second embodiment)

In this embodiment, the structure of forming die for optical element is same as shown in Fig. 1, only the manufacture method difference of mould.

Figure 10 represents to utilize the rete of sputtering method to form schematic representation of apparatus.

In Figure 10, numeral 121 expression vacuum vessels; 122 expressions are connected to oil diffusion pump, the venting port of rotor pump and vacuum valve (not shown); 123 expression base lining bearings; 124 expression base linings; 125 expressions are connected to the airflow rate controller, gas bomb, pressure-regulator, the inlet mouth of valve etc. (not shown).The target of 126 expression source metal or any metallic carbide, a kind of metal nitride and a kind of metal nitrogen carbide; 127 expression targets (what hereinafter retouch is the basic metal target), interior alkali metal containing or alkali metal compound; 128 expression RF radio frequency sources; The device of 129 expression couplings.The base lining rotating mechanism of numeral 310 expression rotation base lining bearings 123.

For example, the operation of said apparatus is as follows:

(1) will include one or both carbon and nitrogen, and the rete of the rare gas element of one or more types forms atmosphere and infeeds vacuum vessel.

(2) radio frequency is added to source metal, or any metallic carbide, the target of metal nitride and metal nitrogen carbide and adding on the basic metal target material.

(3) rete is formed atmosphere gas and become a kind of plasma body, thereby target is carried out sputter.

(4) any contains alkali-metal metallic carbide, and metal nitride and metal nitrogen carbide rete are formed on the surface of base lining.

Sputtering method of the present invention is not limited to said apparatus and system fully.For example, can use the device of DC power supply or system to replace the RF power supply.Also can use magnetron sputtering method, this method is that magnet is arranged near target; Perhaps sputtering method in opposite directions, it is that target is provided with relative to each other.

When adopting metallic target, add to rete by the gas that will contain one or both carbon and nitrogen and form in the atmosphere gas and form any metallic carbide, the thin film layer of metal nitride and metal nitrogen carbide.Using any metallic carbide, when metal nitride, the target of metal nitrogen carbide, the rare gas element that has only use not comprise one or both carbon and nitrogen just can form any metallic carbide, the thin film layer of metal nitride and metal nitrogen carbide.For carburizing and the nitriding effect that improves metal, can suitably add the gas that includes one or both carbon and nitrogen.

That is, metallic carbide can pass through a kind of carbonaceous gas, for example, hydrocarbon gas such as methane, ethane, ethene or acetylene, carbon monoxide or halocarbon add to rete and form in the atmosphere, and gas and metal reaction are formed.Metal nitride can be by with nitrogenous gas, for example, nitrogen, ammonia, or halogenated nitrogen is added to rete and forms in the atmosphere, and gas and metal reaction are formed.The metal nitrogen carbide can form in the atmosphere by carbonaceous gas and nitrogenous gas being added to rete, and these gases and metal reaction are formed.Equally, can be suitably with hydrogeneous or rare gas element (as, helium, argon, neon) gas be added to rete and form in the atmosphere.Especially in sputtering method, wish to add rare gas element, as argon gas with obvious sputter effect.

At any metallic carbide, one or more lithiums in metal nitride and the metal nitrogen carbide, the content of potassium and sodium element are 0.05-5 atom %, select 0.1-2 atom % for use, preferably select 0.5-1 atom % for use.Here the content of mentioning (atom %) be contained in the thin film layer be a kind of lithium, a kind of content of element when potassium and sodium when containing two or more elements in rete, is meant the total content of element.If this content is less than 0.05 atom %, then the adding of one or more lithiums, potassium and sodium element does not have effect.If content is greater than 5 atom %, any metallic carbide then, the thin film layer of metal nitride and metal nitrogen carbide is performance depreciation significantly.

Can utilize the target that forms these elements, or the compound of these elements, such as oxide compound, halogenide, carbide, vitriol, the target of nitrate adds one or more lithiums, potassium and sodium element, this target and any metallic carbide, the target of metal nitride and metal nitrogen carbide is irrelevant, and the target of above-mentioned formation is carried out sputter.Utilize sputter, make lithium, potassium and sodium element, the perhaps compound of these elements gasification, and import in the rete formation atmosphere.Thereby make these elements be added to formed any metallic carbide, in the thin film layer of metal nitride and metal nitrogen carbide.

According to the kind of gas, molding temperature and molded atmosphere are selected any metallic carbide, the thin film layer of metal nitride and metal nitrogen carbide from different thin film layers.Yet, when considering hardness and thermal resistance, wish to use carbide, the carbide of 4A, 5A and 6A group element and element silicon in nitride and the periodictable.In the present embodiment, the 4A group element of periodictable is Ti, Zr and Hf, and the 5A group element is V, Nb and Ta, the element of 6A group is Cr, Mo and W.Silicon is not to be categorized into metal usually.Yet in the present invention, the carbide of silicon, nitride and nitrogen carbide are called as metal nitride in a broad sense respectively, metallic carbide and metal nitrogen carbide.The carbide of the 4A in the periodictable, 5A and 6A group element and silicon, nitride and nitrogen carbide have high hardness (1000 or above Vickers' hardness, be typically 2000 or above hardness), modification is very little when molded.In addition, the carbide of these elements, nitride and nitrogen carbide have high fusing point (1500 ℃ or more than, be typically 2000 ℃ or more than), therefore at high temperature have high stability.So, these compounds seldom with the glass effect, and have high molded weather resistance.

One or more lithiums, potassium and sodium element do not need to be added to any metallic carbide, in the whole thin film layer of metal nitride and metal nitrogen carbide.That is, only these elements need be added to contiguous any metallic carbide, the surface of metal nitride and metal nitrogen carbide.Any metallic carbide, the neighbouring surface place of metal nitride and metal nitrogen carbide thin film layer is meant, is about the zone of hundreds of millimicron apart from the surface of rete.Especially, in surperficial 100nm or zone less than this value, one or more lithiums, the concentration of potassium and sodium element has very big contribution to molded characteristic.So, in the starting stage that forms any metallic carbide, metal nitride and metal nitrogen carbide thin film layer, one or more lithiums, the addition of potassium and sodium element can reduce, and does not perhaps need to add.The final stage that forms at rete just, that is, in having hundreds of millimicron or above thicknesses of layers scope, to one or more lithiums, potassium and sodium element add the concentration (0.05-5 atom %) by the present invention limited.

The example of used in the present invention base lining is to adopt the pottery of oxide compound base-material, for example aluminum oxide and zirconium white; The pottery of carbide and nitride base-material, silicon carbide for example, silicon nitride, titanium carbide, titanium nitride and wolfram varbide; The pottery of WC base-material; And metal, for example molybdenum, tungsten and tantalum.Can form device according to rete, perhaps the molded lens shape of desire is correspondingly determined the shape that base serves as a contrast.For example, when moulded lens, make molded surface be curved surface according to the curvature of lens.Utilize gas-phase synthesizing method can on curved surface, form any metallic carbide, the thin film layer of metal nitride and metal nitrogen carbide.

Below by describing this embodiment for example in detail.(example 1)

In example 1, adopt sputtering method shown in Figure 10 to form the release layer of making by tantalum nitride.

Used die matrix metal is by the SiC sintered article is processed into certain shape, forms polycrystalline Si C rete with CVD again, and the minute surface that molded surface is polished to Rmax=0.04 μ m is formed.This forming mould cleans well, and is placed on in the sputter equipment shown in 10.Tantalum is used as metallic target, and lithium chloride (LiCl) is as the alkali metal source target.After vacuum vessel is evacuated to predetermined vacuum tightness, from gas source inlet 125, with flow velocity nitrogen injection and the argon gas of per minute 20ml.Pressure is 5 * 10 ^-1Pa.RF source 125 (frequency is 13.56MHz) is used for the tantalum target is added the RF output of 800W, the lithium chloride target is added the RF output of 25W.Therefore, base lining bearing 123 rotates with the speed that per minute 10 changes.Utilize aforesaid operations, the thick titanium nitride film of telogenesis one deck 1.5 μ m on the molded surface of die matrix.Be similar to the analytical sample that forms under the laminated one-tenth condition of above-mentioned tantalum nitride membrane with secondary ion mass spectrometer (SIMS) measurement.So, be about 2.0 atom % at the lithium content of the surface of contiguous tantalum nitride membrane layer (in the about 20nm scope in surface).

Utilize this routine forming die for optical element to carry out the compression moulding of glass lens.Use device as shown in Figure 4 used among first embodiment as the glass lens device for molding.

The molded glass of desire is the opticglass SF14 (softening temperature Sp=586 ℃, transition temperature Tg=485 ℃) of flint material, and molded convex lens diameter is 30mm, and diameter is 4 for the thickness ratio.Molded and shaped condition is, a kind of nitrogen atmosphere, and molding temperature is 588 ℃.In carrying out molding process, the demolding performace between forming mould and the molded optical element is good.Die surface is observed with scanning electronic microscope in molded back.As a result, do not find the aliquation or the cracking of rete, and at the lead of glass as the plumbous oxide reduce deposition, perhaps glass itself is not melted yet.That is, mould has good surface property.Equally, molded glass lens has satisfied surfaceness.A kind ofly be same as above-mentioned condition, except not adding forming die for optical element made the lithium this point, and carrying out the glass molding moulding with identical shape with glass material same as described above at the tantalum nitride rete.As a result, the knockout press between mould and the glass is big, thereby causes the cracking of glass and part to be fused to forming mould.(routine 2-5, comparative example 1-4)

In these examples and comparative example, different elements add in the titanium nitride membrane, and their effect is estimated.

Adopt sputtering method shown in Figure 10 to the laminated one-tenth of these titanium nitride membranes.As the die matrix metal, be processed into predetermined shape with WC base material agglomerating carbide.Final forming mould is cleaned well, and be placed in the device shown in Figure 10, carry out the synthetic of titanium nitride.Use titanium as metallic target, and prepare various alkali metal compound targets, make them, therefore these compounds are added in the titanium nitride with the sputter of titanium target.Other synthesis condition is, adds nitrogen and argon gas with the gas velocity of per minute 25ml, is 750W to the radio frequency output of titanium target, is 20W to the RF output of alkali metal compound target, and pressure is 6 * 10 ^-1Pa.Under this condition, form the titanium nitride film that thickness is about 1.2 μ m.So, carry out the compression moulding of glass lens with this forming die for optical element.This molded a kind of continuous molding device (not shown) that utilizes is implemented, and the opticglass SF14 of flint material (softening temperature Sp=586 ℃, transition temperature Sg=485 ℃) is as the molded glass of desire.In nitrogen atmosphere, when 588 ℃ of press temperatures, carry out 5000 times compression molding.It is described that lens shape is similar to example 1.The result is illustrated among Figure 11.

In Figure 11, by to the assessment sample measure the concentration of different elements in titanium nitride, these samples are to be same as under the synthesis condition of forming mould, to form respectively with SIMS.

In routine 2-5, with one or more lithiums, potassium and sodium element add in the titanium nitride film, can obtain moulded product surface property and the molded weather resistance of being satisfied with forming die for optical element.Contrast, in comparative example 1-4, exceed above-mentioned scope owing to add element, the surface property of moulded product and molded weather resistance reduce.In comparative example 1-3, sticking power between mould and the glass is high to the demolding performace between mould and the glass is reduced when molded, and some moulded products are ftractureed.In addition, because the cracking of glass and being adhered on the forming mould just need clean mould when carrying out molded test.In comparative example 4, the impaired significantly and aliquation of titanium nitride film.Thus, the surface property of molded glass degenerates, and this will make molded glass be unsuitable for actual use.As mentioned above, by with one or more lithiums, potassium and sodium element are added in the titanium nitride film, can obtain as forming die for optical element satisfied molded product surface performance and molded weather resistance.(routine 6-11, comparative example 5 and 6)

In these examples and comparative example, form various release layer, and they are made an appraisal.

Adopt example 2 described sputtering methods to form these release layers.

The die matrix metal at first is processed into predetermined shape.Final mould cleans well, and is placed in the device shown in Figure 10, forms thin release layer.When rete forms, use different metallic targets, selected gas is as follows.

(1) when metal nitride forms, nitrogen is 20ml/min, and argon gas is 20ml/min.

(2) when metallic carbide form, methane is 20ml/min, and argon gas is 20ml/min.

(3) when the metal nitrogen carbide formed, nitrogen was 10ml/min, and methane is 10ml/min, and argon gas is 20ml/min.

(4) when metallic diaphragm forms, argon gas is 30ml/min.

Equally, for lithium is added release layer, use lithium fluoride as the alkali metal source target.

Other synthesis condition is, is 800W to the RF output of metallic target, is 25W to the RF output of alkali metal source target, and pressure is 3.5 * 10 ^-2Pa, thicknesses of layers are about 1.2 μ m.So, carry out the compression moulding of glass lens with this forming die for optical element.This moulding is undertaken by an apparatus for continous formation, and flint base-material opticglass SF14 (softening temperature Sp=586 ℃, transition temperature Tg=485 ℃) is used as the molded glass of desire.In nitrogen atmosphere, when press temperature was 588 ℃, compression moulding was carried out 5000 times.The shape of lens is similar to the shape of example 1.The results are shown in shown in Figure 12.

To utilizing the sample to be tested that forms respectively under the synthesis condition of forming mould being same as, with the lithium concentration in the SIMS spectrometer measurement release layer.As a result, lithium concentration is 0.5-1.2 atom % in all these samples.

In routine 6-11, utilize arbitrary group of 4A, 5A and the element of 6A and the carbide of silicon of periodictable, the thin film layer of nitride or nitrogen carbide can be obtained moulded product surface property and molded weather resistance as the satisfaction of optical element mold.Otherwise, in comparative example 5 and 6, because the concentration of lithium is outside above-mentioned scope, so the surface property of moulded product and molded weather resistance reduce.In comparative example 5, since very strong with the effect of glass, so the sticking power between mould and the glass is very big.So the demolding performace when molded between mould and the glass descends, some molded glasses produce cracking.In addition, because glass ftractures and adheres to mould, just need when molded test, clean well mould.In comparative example 5 and 6, may be because the hardness of rete be low, rete is damaged when molded carrying out.So the surface property of molded glass descends, the product of being made by this molded glass is not suitable for actual use.(routine 12-15, comparative example 7 and 8)

In these examples and comparative example, form the release layer of making by the carborundum films layer with sputtering method.

Utilize sputter equipment shown in Figure 10 to form these silicon carbide film layer.

In these examples and comparative example, silicon carbide is used as the metal nitride target, boronation lithium (LiB ₂) as the alkali metal source target, so lithium is added in the carborundum films layer.In these examples and comparative example, the centre that forms at rete adds to boronation lithium target with radio frequency, only lithium is added to the near surface place of each carborundum films layer thus.

Be processed to the mould metal base that the carbide material of predetermined shape makes by sintering and be placed in the device shown in Figure 10, and form the carborundum films layer.Formation condition is that gas velocity is: methane 10ml/min, and argon gas 30ml/min, 200 ℃ of base lining temperature are 800W to the RF output of carbonization silicon target, are 25W to the RF output of boronation lithium, pressure is 5 * 10 ^-1Pa.The centre that forms at rete adds to boronation lithium target with radio frequency, utilizes to change the silicon carbide film layer that the working hour forms the adding lithium with different thickness.Point out that the silicon carbide film layer that does not add lithium is set at 1.2 μ m with the total thickness that adds the lithium silicon carbide film layer.

Utilize the synthesis condition identical with above-mentioned forming mould, the sample to be tested of Xing Chenging respectively adds the elemental lithium concentration of the silicon carbide film layer of lithium by the SIMS spectrometry, and its concentration is about 2.1 atom %.

Utilize this forming mould to carry out the test of molded and shaped weather resistance.It is molded to adopt a continuous molding device to carry out, and the molded glass of desire is the opticglass SK12 (softening temperature Sp=672 ℃, transition point Tg=550 ℃) of crown board base-material.It is 35mm that the convex lens that are molded have diameter, and diameter is 4 with the thickness ratio.In nitrogen atmosphere, when 620 ℃ of press temperatures, carry out 5000 compression moulding.The results are shown in Figure 13.

In routine 12-15, the demolding performace when molded between mould and the molding of optical elements is good.After molded, during with the sem observation die surface, do not find the aliquation or the cracking of rete, there is not glass to be melted yet.Equally, the glass lens that is molded has one and is satisfied with practical surfaceness.In comparative example 7 and 8, the content of lithium is less than 0.1 μ m in silicon carbide film layer, and the knockout press between mould and the glass is strong, so the glass cracking, segment glass is fused to mould.(routine 16-20, comparative example 9 and 10)

In these examples and comparative example, the concentration of element that is added in the titanium nitride thin rete is estimated.

Utilize sputtering method shown in Figure 2 to form titanium nitride.

The mould metal base is processed into predetermined shape.Final mould is cleaned well, and be placed in the device shown in Figure 10, form the titanium nitride thin rete.Metal titanium and lithium fluoride are as target, and the RF power that adds on the lithium fluoride in the rete forming process, by change changes the amount that adds the lithium in the titanium nitride.Synthesis condition is that gas velocity is: nitrogen is 20ml/min, and argon gas is 30ml/min, and output is 750W to the RF of titanium target, and pressure is 4 * 10 ^-1Pa.Under this condition, the thickness that forms titanium nitride film is about 1 μ m.Utilize this forming die for optical element to carry out the compression moulding of glass lens.It is molded to adopt a kind of continuous molding device to carry out, and the molded glass of desire is the opticglass SF14 (softening temperature Sp=586 ℃, transition point Tg=485 ℃) of flint base-material.In nitrogen atmosphere, when 588 ℃ of press temperatures, carry out 5000 times and be molded as type.Lens shape is similar to the results are shown in shown in Figure 14 in the example 1.

In Figure 14, by measuring the elemental lithium concentration of sample to be tested acquisition in titanium nitride film, these samples are to form respectively under the synthesis condition identical with above-mentioned forming mould, and record with the SIMS spectrum.

In routine 16-20, by the elemental lithium concentration of setting 0.05 to 5 atom % obtain as forming die for optical element moulded product surface property and molded weather resistance.Otherwise, in comparative example 9 and 10, because the concentration of elemental lithium is not in above-mentioned scope, so moulded product surface property and molded weather resistance all descend.In comparative example 9, because low elemental lithium concentration, cause the sticking power between forming mould and the glass to become big, thereby the demolding performace between mould and the glass descend some molded glass products crackings when molded.In addition, because the glass cracking, and be attached on the forming mould, thus need be in molded process of the test cleaning mold.In comparative example 10, because high elemental lithium concentration is damaged titanium nitride film.This is at the wearing and tearing and the aliquation that carry out can causing when molded rete.So the surface property of molded glass descends, resulting molded glass is not suitable for actual use.That is, when the concentration of adding element was lower than 0.05 atom %, the demolding performace when molded between mould and the glass was unsatisfied.When the concentration of adding element was higher than 5 atom %, the film quality variation of titanium nitride thin rete caused the wearing and tearing or the aliquation of rete.As mentioned above, one or more are selected from lithium, when the interpolation concentration of potassium and sodium element is set in 0.05-5 atom %, can obtain satisfied moulded product surface property and molded weather resistance as forming die for optical element.

As above described in detail, when forming mould according to the present invention was used for the molded glass optical element, the demolding performace between glass and the mould was goodish.Thus, might obtain to have high surface planarity and surface accuracy, high light transmittance, the moulded product of high form accuracy.In addition, promptly use this mould to carry out long compression moulding repeatedly, also can not produce aliquation or cracking, and damage such as rete.This has just improved the weather resistance of mould.

In the making method of the forming die for optical element of manufacturing glass optical component with above-mentioned forming mould, might manufacture with low cost and neither make the rete damage, do not make the forming die for optical element of the air spots face degree decline of molded glass yet.This will boost productivity and reduce cost.

The present invention is not limited to the above embodiments, can makes various changes and improvements within the spirit and scope of the present invention.So following claim is to public's bulletin scope of the present invention.

Claims

1. forming die for optical element, be used for making optical element by die forming, it is characterized in that: at least one molded surface, form one and contain the film of elemental lithium or lithium compound as release layer, this film is made of the material of selecting from TaN, TiN, ZrN, TiC, TiCN, MoC, SiC, SiN and CrC, and in this film, the content of elemental lithium or lithium compound is 0.05～5 atom %.

2. method of making forming die for optical element, be used for making optical element by die forming, it is characterized in that: adopt the source metal material that comprises elemental lithium or lithium compound, on at least one molded surface, form a film that contains elemental lithium or lithium compound with ionization coating or sputter method of coating as release layer, this film is made of the material of selecting from TaN, TiN, ZrN, TiC, TiCN, MoC, SiC, SiN and CrC, and in this film, the content of elemental lithium or lithium compound is 0.05～5 atom %.