CN107861333A

CN107861333A - Photomask blank, photomask blank manufacture method, using its photo mask manufacturing method and display device manufacture method

Info

Publication number: CN107861333A
Application number: CN201710794878.0A
Authority: CN
Inventors: 坪井诚治; 浅川敬司; 中村真实; 阿山兼士; 安森顺; 安森顺一
Original assignee: Hoya Corp; Hoya Electronics Malaysia Sdn Bhd
Current assignee: Hoya Corp; Hoya Electronics Malaysia Sdn Bhd
Priority date: 2016-09-21
Filing date: 2017-09-06
Publication date: 2018-03-30
Also published as: TWI711876B; JP2018049111A; KR102234301B1; KR20180032196A; JP6632950B2; TW201821898A

Abstract

The present invention provides the photomask blank and its manufacture method for verticalization that can make mask pattern cross sectional shape.The present invention also provides the manufacture method of the manufacture method and display device using its photomask.The photomask blank of the present invention has transparency carrier (1), light shield layer (2) and antireflection layer (3), light shield layer (2) is formed by the chromium compound containing chromium and nitrogen, antireflection layer (3) is by containing chromium, the chromium compound of nitrogen and oxygen is formed, the content of the chromium contained in antireflection layer (3) is less than the content of the chromium contained in light shield layer (2), the stack membrane of antireflection layer (3) multilayer that has been lamination, oxygen content of the oxygen content contained by more than the lower layer part (31) of the light shield layer side of antireflection layer (3) contained by the upper layer part (32) of the face side of antireflection layer (3), there is the region for being substantially free of carbon in the face side of upper layer part (32), in the region, oxygen continuously increases towards most surface, and oxygen is more than 5 relative to the maximum of the ratio (O/N) of nitrogen.

Description

Photomask blank, the manufacture method of photomask blank, the photomask manufacturer using it The manufacture method of method and display device

Technical field

The present invention relates to photomask blank, the manufacture method of photomask blank and (transfer is with covering using its photomask Mould) manufacture method and used the photomask manufactured by the manufacture method display device manufacture method.

Background technology

For example, for the FPD (FPD with LCD (liquid crystal display, Liquid Crystal Display) for representative Device, Flat Panel Display) etc. for display device, not only quickly carry out large screen, wide viewing angle, Er Qiezheng Quickly carrying out High precision, at a high speed displayization.For the High precision, one of key element of displayization and needs is to manufacture at a high speed The electronic circuit patterns such as fine and high dimensional accuracy element, wiring.The patterning of the display device electronic circuit makes mostly Use photoetching process.Therefore, it is necessary to form the display device manufacture photomask of fine and high-precision pattern.

From the viewpoint of the drawing disposal ability of fine degree and mask pattern for improving the pattern used, display device system Make with photomask generally mask pattern drawing in using the laser that wavelength is 413nm etc..Moreover, for the shape in laser drawing Into the mask pattern of high dimensional accuracy, be formed at mask pattern (shading film figure) on the transparency carriers such as synthetic quartz generally by Mask pattern is formed with photomask, and the mask pattern photomask has the laminated construction of light shield layer and antireflection layer, described Light shield layer blocks the exposure light (the exposure light used in photoetching process) during manufacture display device, and the antireflection layer reduces above-mentioned sharp The reflection of light drawing light.The reflection of laser drawing light can be suppressed using the antireflection layer being formed on light shield layer, so as to shape Into the mask pattern of high dimensional accuracy.

Patent Document 1 discloses on such photomask blank and using its photomask manufacture method and The technology of the manufacture method of display device.

Prior art literature

Patent document

Patent document 1：Japanese Unexamined Patent Publication 2016-105158

The content of the invention

The invention problem to be solved

In order to reduce picture element flaw, circuit defect and above-mentioned display device is manufactured with high finished product rate, it is desirable to pattern accuracy High photomask.Covered it is therefore desirable to disclosure satisfy that the optical property of needs, defect are few and can form the light of high-precision pattern Mold base material.

One of the main reason for influenceing optical property, the pattern accuracy of photomask is verticalization of the cross sectional shape of pattern.

In general, the transfer in display device manufacture is greater than required by semiconductor device manufactures with the size of pattern The size of transfer pattern.But as semiconductor device manufacture photomask, usually using reduced projection mask, with this Relatively, as display device manufacture photomask, usually using equimultiple exposure mask (equimultiple mask).Due to the mask multiplying power Difference, for display device manufacture photomask, according to the length-width ratio of mask pattern (the height H of mask pattern with it is wide Spend the ratio between W：H/W relation), the width of the tilting zone of the cross sectional shape of mask pattern are used in transfer relative to reduced projection The width increase of mask.In addition, for display device manufacture with for photomask (equimultiple mask), the section shape of mask pattern The inclination of shape also impacts itself to transfer performance.Therefore, the fine pattern in reply display device manufacture, which is formed, requires Aspect, this is set to be inclined nearly in being vertically very important as far as possible.

In view of the foregoing, it is an object of the invention to provide a kind of photomask blank and its system that can manufacture photomask Method is made, the photomask can form the mask pattern with subvertical cross sectional shape, thus, it is possible to high-precision landform Into fine pattern.In addition, manufactured the present invention also aims to provide one kind using photomask blank and its manufacture method State the method for photomask and the manufacture method of display device.

The method for solving problem

(scheme 1)

A kind of photomask blank, it has the transparency carrier, described by being formed to the substantially transparent material of exposure light The antireflection layer on light shield layer and the light shield layer on bright substrate, wherein, the light shield layer is by the chromaking containing chromium and nitrogen Compound is formed, and the antireflection layer is formed by the chromium compound containing chromium, nitrogen and oxygen, and the chromium contained in the antireflection layer contains Amount is less than the content of chromium contained in the light shield layer, the stack membrane of the antireflection layer multilayer that has been lamination, the antireflective Oxygen of the oxygen content contained by more than the lower layer part of the light shield layer side of the antireflection layer contained by the upper layer part of the face side of layer Content, there is the region for being substantially free of carbon in the face side of the upper layer part, in the region, oxygen continuously increases towards most surface Add, and oxygen is more than 5 relative to the maximum of the ratio (O/N) of nitrogen.

(scheme 2)

According to the photomask blank described in scheme 1, wherein, the oxygen relative to the ratio (O/N) of nitrogen minimum value for 2 with On.

(scheme 3)

Photomask blank according to scheme 1 or 2, wherein, there is adjustment between the transparency carrier and light shield layer The transmissivity adjustment layer of transmissivity.

(scheme 4)

Photomask blank according to scheme 1 or 2, wherein, there is adjustment between the transparency carrier and light shield layer The phase adjustment layer of phase difference.

(scheme 5)

Photomask blank according to scheme 3 or 4, wherein, the transmissivity adjustment layer and the phase adjustment layer bag Containing the material to the light shield layer with etching selectivity.

(scheme 6)

According to the photomask blank any one of scheme 1~5, wherein, formed with against corrosion on the antireflection layer Oxidant layer.

(scheme 7)

According to the photomask blank described in scheme 6, wherein, the resist layer is coated with without the against corrosion of surfactant Agent.

(scheme 8)

A kind of manufacture method of photomask blank, it is the manufacturer of the photomask blank any one of scheme 1~7 Method, this method include：Prepare the process of the transparency carrier, form the light shield layer on the main surface of the transparency carrier Process and the process that the antireflection layer is formed on the light shield layer, this method also include：Including carbon dioxide gas Body, nitrogenous gas mixed gas atmosphere in the lower layer part of the antireflection layer formed by using the sputtering of chromium target Process, and comprising oxygen-containing gas, nitrogenous gas mixed gas atmosphere in formed by using the sputtering of chromium target The process of the upper layer part of the antireflection layer.

(scheme 9)

There is following process to manufacture photomask for a kind of manufacture method of photomask, this method：Appoint in operational version 1~5 Photomask blank described in one or the photomask blank by the manufacture method manufacture described in scheme 8, in the photo blanks The process that resist layer is formed on material；The process of pattern desired by being drawn to the resist layer；Developed, covered in the light The process that Resist patterns is formed on mold base material；And based on the Resist patterns to the light shield layer and the antireflection layer It is etched, so as to form the process of pattern.

(scheme 10)

A kind of manufacture method of photomask, the photomask blank described in this method operational version 6 or 7, and there is following work Sequence manufactures photomask：The process of pattern desired by being drawn to the resist layer；Developed, on the photomask blank The process for forming Resist patterns；And the light shield layer and the antireflection layer are lost based on the Resist patterns Carve, so as to form the process of pattern.

(scheme 11)

The manufacture method of photomask according to scheme 9 or 10, wherein, the resist layer is coated with lives without surface The resist of property agent.

(scheme 12)

A kind of manufacture method of display device, this method include：Exposure process, any one of scheme 9~11 institute will be passed through The photomask of the manufacture method manufacture for the photomask stated is placed in the mask platform of exposure device, will be formed on the photomask Transfer is transferred to the resist being formed on display device substrate with pattern exposure.

The effect of invention

Photomask is manufactured by using the photomask blank of the present invention, the shape of patterned section can be provided close to vertically And the photomask that transferring properties, miniaturization are appropriate.In addition, manufacture display device by using the photomask, can with height into Product rate manufactures the display device of fine.

Brief description of the drawings

Fig. 1 is the major part sectional structure chart of the schematic construction for the photomask blank for showing embodiments of the present invention 1.

Fig. 2 is the schematic construction of the type sputter equipment in upright arrangement for the film forming for illustrating the ability to the photomask blank for the present invention Schematic diagram.

Fig. 3 (a)~(e) is the major part cross-section structure for the photomask manufacturing process for showing embodiments of the present invention 2 Figure.

Fig. 4 is the performance plot of the Elemental redistribution of the film for the photomask blank for showing embodiment 1.

Fig. 5 is the figure of the ratio of the Elemental redistribution of nitrogen and oxygen in the photomask blank for show embodiment 1.

Fig. 6 is the cross-section photograph of the cross sectional shape of the marginal portion for the shading film figure for showing embodiment 1.

Fig. 7 is the performance plot of the Elemental redistribution of the film for the photomask blank for showing comparative example.

Fig. 8 is the cross-section photograph of the cross sectional shape of the marginal portion for the shading film figure for showing comparative example.

Symbol description

1 transparency carrier

2 light shield layers

2a shading layer patterns

3 antireflection layers

31 lower layer parts

32 upper layer parts

3a antireflection layer patterns

4 resist films

4a Resist patternss

100 photomask blanks

200 photomasks

300 sputter equipments in upright arrangement

Embodiment

Hereinafter, embodiments of the present invention are specifically illustrated referring to the drawings.It should be noted that following implementation Mode is form when making present invention materialization, and the present invention is not limited in the range of it.

The ＞ of ＜ embodiments 1

In embodiment 1, display device manufacture is illustrated with photomask blank and its manufacture method.

Fig. 1 is the diagrammatic cross-section for the membrane structure for showing display device manufacture photomask blank 100.The photomask blank 100 in terms of big from the point of view of include with lower part：Made of to the transparent material of exposure light transparency carrier 1, be formed at it is transparent Light shield layer 2 on substrate 1 and the antireflection layer 3 being formed on light shield layer 2.

Light shield layer 2 is made up of the chromium compound at least containing chromium and nitrogen, has the function of absorbing exposure light and shading.As The chromium compound of light shield layer 2 is formed, chromium nitride (CrN), nitrogen oxidation chromium (CrON) etc. can be used.By containing light shield layer 2 Nitrogen, the wet etch rate to chromium etching solution can be improved.In addition, by making light shield layer 2 contain nitrogen, can be using film forming as crystal grain control Small film is made.From the aspect of membrane stress is relaxed, light shield layer 2 is preferably set to contain nitrogen.Consider from above-mentioned viewpoint, be preferably free of The chromium nitride (CrN) of oxygen, in the case of nitrogen oxidation chromium (CrON), oxygen content is 10 atom %, preferably below 8 atom %, More preferably below 5 atom %.

It should be noted that each element that can make to contain in light shield layer 2 forms composition gradient.Forming composition gradient In the case of, composition gradient (distribution) can be continuously formed, can also hierarchically form composition distribution.It is continuously formed in composition When gradient is distributed, there are following characteristics：The wet etch rate of mask pattern film thickness direction also continuously changes, readily available flat It is sliding and close to vertical mask pattern shape.On the other hand, when hierarchically forming composition distribution, there are following characteristics：Hide The film formation process of photosphere is stable, is easy to improve manufacture quality, therefore can simplify PQC (process quality control, Process Quality Control) required for process.

Antireflection layer 3 is made up of the chromium compound containing chromium, nitrogen and oxygen, and having prevents that mask pattern drawing light (paint by laser Figure light) reflection function.Prevented in addition, antireflection layer 3 also has concurrently when manufacturing display device to the function of exposure light reflection. The chromium content of antireflection layer 3 is less than the chromium content of light shield layer 2.Or light shield layer 2 is by least containing chromium and nitrogen in chromium, nitrogen and oxygen Chromium compound form, the oxygen content of antireflection layer 3 is more than the oxygen content of light shield layer 2.This is because, the chromium of antireflection layer 3 contains When amount is less than the oxygen content of light shield layer 2 more than the chromium content of light shield layer 2 or the oxygen content of antireflection layer 3, mask pattern is painted Figure light (laser drawing light), the reflectivity of exposure light increase.

The stack membrane that antireflection layer 3 is formed by the upper layer part 32 of face side and the lamination of lower layer part 31 of the side of light shield layer 2 is formed. By the way that stack membrane is made, the antireflection layer 3 that can obtain the thickness for needing optical property can be formed as to the film of densification (with low work( The sputtering power of rate is formed).Thereby, it is possible to suppress the generation of film defect, and can be made to possess high resistance to chemical reagents (for profit Cleaned before the resist coating that the decoction such as the washing lotion of sulfur acid, ozone washing lotion as sulfuric acid or sulfuric acid/hydrogen peroxide is carried out Tolerance) antireflection layer 3.

The oxygen content contained in the upper layer part 32 of antireflection layer 3 is more than the oxygen content contained in lower layer part 31, in upper layer part 32 face side, which has, is substantially free of the region of carbon, and in this region, oxygen continuously increases towards most surface, and oxygen relative to The maximum of the ratio (O/N) of nitrogen is more than 5.By structure as formation, the cross sectional shape of mask pattern can be made vertical Change.

The formation of mask pattern is carried out in the following manner：After photomask blank is cleaned, formed on antireflection layer 3 anti- Oxidant layer is lost, antireflection layer 3 is etched based on the Resist patterns formed on the resist layer.

In the past, the resist containing surfactant has been used in the formation of the resist layer.This is anti-in order to improve Lose wetability during agent coating.However, found out, when making resist layer filming to transfer the miniaturization of pattern, The surfactant contained in the resist is deposited for improving resist coating performance (film thickness uniformity, defect reduction etc. in face) In harmful effect, when attempting to be masked the formation of pattern using the resist without surfactant, comparison such as below Shown in example (Fig. 8), the cross sectional shape of mask pattern forms the taper with very long end.It is considered that its reason exists In, because resist and photomask blank surface (antireflection layer) adaptation the problem of etc., wet etching solution is immersed in resist The interface of film and photomask blank (antireflection layer), causes heavy corrosion.

The result that the problem is studied in detail is as follows：As shown in following embodiment, in the upper of antireflection layer 3 The face side in layer portion 32 forms the region for being substantially free of carbon, and in the region, oxygen continuously increases towards most surface, and oxygen is relative It is more than 5 in the maximum of the ratio (O/N) of nitrogen, thus can improves the close of resist and photomask blank surface (antireflection layer) Close property so that the cross sectional shape of mask pattern be improved significantly (verticalization).In addition, by improving ratio of the oxygen relative to nitrogen Rate, the film of densification can be formed, so as to which resistance to chemical reagents also excellent film is made.

It should be noted that in Fig. 1, upper layer part 32 and lower layer part 31 are described in the form of being divided into 2 films, It may also be the layer of consecutive variations.It can also be more than 3 layers of stack membrane.As long as antireflection layer 3 is on the surface of upper layer part Side forms the stack membrane in the region for being substantially free of carbon, and in this region, oxygen continuously increases towards most surface, and Oxygen is more than 5 relative to the maximum of the ratio (O/N) of nitrogen.

From the viewpoint of cross sectional shape verticalization of mask pattern is made, in the face side of the upper layer part 32 of antireflection layer 3 Be substantially free of in the region of carbon, preferably oxygen relative to the ratio (O/N) of nitrogen minimum value be more than 2, further preferred oxygen Minimum value relative to the ratio (O/N) of nitrogen is more than 2.5.

It should be noted that for each element contained in antireflection layer 3, along film thickness direction continuously (or point Level ground) when forming composition distribution (composition gradient), the section of the shading film figure after wet etching is smoothened, therefore preferably, CD precision is also improved.

The photomask being made up of light shield layer 2 and antireflection layer 3 can be that binary mask (binary mask) uses photomask, Can also be (for example, half-tone type phase shift mask (Attenuated Phase Shift Mask), sharp Vincent in phase shifting mask Type phase shifting mask (Levenson Mask, Alternating Phase Shift Mask)) with phase shift film (adjustment phase place difference Phase adjustment layer) or multi-stage grey scale mask (Multi-level Gradation Mask) transmission rate controlling membrane (adjustment transmission The transmissivity adjustment layer of rate) on or below the photomask that is formed.

Half-tone type phase shift mask in phase shifting mask, form transmissivity between transparent substrate and shading film figure In the case of the multi-stage grey scale mask for controlling film figure, in order that forming the phase shift film of mask pattern, transmission rate controlling membrane is carried out The transmissivity control of transmitted light and/or phase controlling, set adjustment transmissivity or adjustment between transparency carrier 1 and light shield layer 2 At least functional membrane of any one in phase.As the functional membrane, it can be applicable in silicon (Si) and contain in metal, oxygen, nitrogen, carbon or fluorine At least material of any one, the material are the materials for having etching selectivity to the chromium material for forming the material of light shield layer 2.Example Such as, the metal silicides such as MoSi, the oxide of metal silicide, the nitride of metal silicide, metal silicide are applied Nitrogen oxides, the carbonitride of metal silicide, the oxycarbide of metal silicide, metal silicide carbon nitrogen oxide, SiO、SiO₂And SiON etc..For SiO, SiO₂For, transparency carrier 1 be synthetic quartz in the case of, by with transparency carrier 1 Identical element is formed, but due to interatomic bond styles difference etc., etch-rate is different from the etch-rate of substrate, can Accurately carry out optical distance (etch depth) control important in phase-difference control.It should be noted that the functional membrane can To be the stack membrane being made up of the above-mentioned film enumerated as functional membrane.

Shading film figure containing chromium can be etched by the processing of the functional membrane is made mask to carry out.Therefore, exist In the processing of functional membrane, compared with the photomask being made up of light shield layer 2 and antireflection layer 3, functional membrane can use make etching fast The wet etching solution that rate is accelerated.As such wet etching solution, can enumerate for example：Containing selected from hydrofluoric acid, fluosilicic acid and At least one of hydrofluoric acid ammonium fluorochemical and at least one containing water or in hydrogen peroxide, nitric acid and sulfuric acid The solution of kind oxidant.It can specifically enumerate：The erosion obtained from the mixed solution of pure water dilute hydrofluoric acid ammonium and hydrogen peroxide Carve liquid, etching solution etc. obtained from mixed fluoride ammonium in hydrofluoric acid aqueous solution.

Hereinafter, the manufacturing process of photomask blank is described in detail.

1. preparatory process

First, transparency carrier 1 is prepared.

As long as the material of transparency carrier 1 is to exposure light to be used with translucency and with rigid material, It is not particularly limited.It can enumerate for example：Synthetic quartz glass, soda-lime glass, alkali-free glass.In addition, in order to be made it is flat and Smooth main surface, can suitably carry out including rough polishing manufacturing procedure, precise polished manufacturing procedure, partial operation as needed Process and the polishing for contacting polishing process.Then, cleaned, remove foreign matter, the pollutant on the surface of transparency carrier 1. As cleaning, such as hydrofluoric acid, fluosilicic acid, sulfuric acid, sulfuric acid/hydrogen peroxide (SPM), ammonia, ammonia/hydrogen peroxide can be used (APM), OH free radicals rinse water, Ozone Water etc..

2. photomask formation process

Then, the mask pattern being made up of chromium based material is formed on the main surface of transparency carrier 1 by sputtering method to be formed Use photomask.Photomask is made up of the stack membrane with light shield layer 2 and antireflection layer 3, in addition, antireflection layer 3 is again formed as folding Tunic.It should be noted that light shield layer 2 can also be formed with stack membrane.The lamination number of light shield layer 2 and antireflection layer 3 is without spy Do not limit, here, enter by by 1 layer of light shield layer 2 and 2 layers of antireflection layer 3, total exemplified by the formation process of 3 layers of situation about being formed Row describes in detail.

First, film formation device is illustrated.

Fig. 2 is the schematic diagram of one for showing the sputter equipment for forming light shield layer 2 and antireflection layer 3.

Sputter equipment 300 shown in Fig. 2 is type in upright arrangement, by input chamber LL, the 1st sputtering chamber SP1, surge chamber BU, the 2nd sputtering Room SP2 and this 5 rooms of output room UL are formed.This 5 rooms continuously configure successively.

The pallet 301 of transparency carrier 1 is placed with substrate holder with given translational speed (travelling speed) along arrow Transported according to input chamber LL, the 1st sputtering chamber SP1, surge chamber BU, the 2nd sputtering chamber SP2, output room UL order in direction.

Input chamber LL is separated by baffle plate 311 and 312 respectively with the 1st sputtering chamber SP1, the 2nd sputtering chamber SP2 and output room UL. In addition, input chamber LL, each sputtering chamber SP1/2, surge chamber BU and output room UL are connected with the exhaust apparatus being exhausted and (not schemed Show).

Sputtering target material 331,332 is provided with 1st sputtering chamber SP1, gas introduction port (not shown) corresponding with each target sets In the upstream side of each target (left side in accompanying drawing).In addition, sputtering target material 333,334 is provided with the 2nd sputtering chamber SP2.With sputtering Gas introduction port (not shown) corresponding to target 333 is located at the upstream side (left side in accompanying drawing) relative to target, with sputtering target Gas introduction port (not shown) corresponding to material 334 is located at the downstream (right side in accompanying drawing) relative to target.

Next, to forming light shield layer 2 and antireflection layer 3 (upper layer part 32 and lower floor using the type sputter equipment 300 in upright arrangement Portion 31) process illustrate.

First, pallet 301 is transported into input chamber LL.

After the inside of sputter equipment 300 is reached given vacuum, from the gas introduction port for being located at the 1st sputtering chamber SP1 Imported with given flow to the film forming gas required for the progress film forming of light shield layer 2, in addition, applying what is given to sputtering target material Sputtering power, pallet 301 is set to pass through the top of sputtering target material 331 and 332 with given speed S1.As sputtering target material 331 and 332, using chromium or mainly contain the target of chromium.As the target for mainly containing chromium, there are chromium, chromium nitride, acidifying chromium etc., due to logical Crossing the reactive sputtering of supply gas progress easily controls as desired composition distribution gradient, therefore is used herein Chromium is as target.In order to form chromium nitride (CrN) layer containing chromium and nitrogen, nitrogen oxidation chromium (CrON) layer as light shield layer 2, from The gas for being located at the 1st sputtering chamber SP1 gas introduction port supply is at least to contain nitrogen (N₂) gas, can add as needed The non-active gas such as argon (Ar) gas.As non-active gas, in addition to argon gas, also helium (He), neon (Ne), Krypton (Kr) one or more can and xenon (Xe) etc., be selected therefrom as needed.The control of the composition distribution of film thickness direction can be with Carried out by the configuration of gas introduction port, method for supplying gas etc..

Process more than, when near the sputtering target material that pallet 301 passes through the 1st sputtering chamber SP1, splashed by reactivity Penetrate, given thickness and the light shield layer 2 being made up of chromium based material are formed on the main surface of transparency carrier 1.Now, for wavelength The OD values of 436nm light are preferably more than 1.0.This is because, even if being transferred with high light exposure (high dose), can also prevent Transfer defect only occurs.The OD values can be ensured by forming, the OD values can also be ensured by the control of thickness.

Then, pallet 301 is moved to the 2nd sputtering chamber SP2 by surge chamber BU.

Lower layer part 31 is carried out needed for film forming from being imported with 333 corresponding gas introduction port of sputtering target material with given flow The film forming gas wanted, and apply given sputtering power to sputtering target material 333.

In this condition, pallet 301 is made to pass through the top of sputtering target material 333 with given speed S2 to form lower layer part 31. As sputtering target material 333, chromium target is used.In addition it is also possible to use the target for being properly added thing containing nitrogen, oxygen etc. in chromium. In order to form nitrogen oxidation chromium (CrON) layer, the carbon nitrogen containing chromium, oxygen, nitrogen and carbon containing chromium, oxygen and nitrogen as lower layer part 31 Chromium oxide (CrCON) layer, from the gas supplied with 333 corresponding gas introduction port of sputtering target material be at least containing oxygen-containing gas and The gas of nitrogenous gas, the non-active gas such as argon gas (Ar) can be added as needed.As non-active gas, except argon gas with Outside, also helium (He), neon (Ne), Krypton (Kr) and xenon (Xe) etc., can select a kind or more therefrom as needed Kind.It is containing the aerobic gas as constitution element, nitrogenous gas refers to contain gas of the nitrogen as constitution element as oxygen-containing gas Body.Here, oxygen-containing gas has such as oxygen (O₂), carbon dioxide (CO₂) etc., nitrogenous gas has such as nitrogen (N₂), dioxy Change nitrogen (NO₂) and nitric oxide gas (NO) etc..The control of the composition distribution of film thickness direction can pass through gas introduction port Configuration, method for supplying gas etc. carries out.Here, when carrying out film forming with the small condition of sputtering power, densification can be formed Film, it is not easy to produce film defect.

Film defect is not likely to produce in order to which lower layer part 31 to be formed to the film of densification, the condition of sputtering power is preferably set to It is 3.0kW following.Reduction and productivity in view of film defect, are preferably set to more than 1.0kW and below 3.0kW by sputtering power, Further preferably it is set to more than 1.0kW and below 2.5kW.

Process more than, when pallet 301 is by near sputtering target material 333, by reactive sputtering, in light shield layer Given thickness and the lower layer part 31 (CrON layers, CrCON layers) being made up of the chromium compound containing chromium, nitrogen and oxygen are formed on 2.From cut From the viewpoint of verticalization of face shape, lower layer part 31 is preferably the carbon nitrogen oxidation chromium (CrCON) containing chromium, oxygen, nitrogen and carbon.Make To form gas during lower layer part 31, preferably use and contain carbon dioxide (CO₂), nitrogen (N₂) and non-active gas (Ar Deng) mixed gas.

Then, pallet 301 moves to sputtering target material 334.From with 334 corresponding gas introduction port of sputtering target material with given Flow imports the film forming gas carried out to upper layer part 32 required for film forming, and applies given sputtering power.In this condition, Pallet 301 is set to pass through the top of sputtering target material 334 with given speed S3 to form upper layer part 32.As sputtering target material 334, use Chromium target.In addition it is also possible to use the target for being properly added thing containing aerobic, nitrogen etc. in chromium.In order to be formed as upper layer part 32 Containing chromium, oxygen and nitrogen and upper layer part 32 face side have be substantially free of carbon region nitrogen oxidation chromium (CrON) layer, Carbon nitrogen oxidation chromium (CrCON) layer, it is at least containing oxygenous from the gas supplied with 334 corresponding gas introduction port of sputtering target material The gas of body and nitrogenous gas, the non-active gas such as argon gas (Ar) can be added as needed.As non-active gas, except argon Beyond gas, also helium (He), neon (Ne), Krypton (Kr) and xenon (Xe) etc., can select therefrom as needed a kind or It is a variety of.Refer to that, containing the aerobic gas as constitution element, nitrogenous gas refers to contain nitrogen as constitution element as oxygen-containing gas Gas.Oxygen-containing gas has such as oxygen (O₂), carbon dioxide (CO₂) etc., nitrogenous gas has such as nitrogen (N₂), dioxy Change nitrogen (NO₂) and nitric oxide gas (NO) etc..It should be noted that in order to which there is essence in the face side of upper layer part 32 Upper carbon-free region, as oxygen-containing gas, preferably using oxygen (O₂), as nitrogenous gas, preferably using nitrogen (N₂)。 Gas when i.e., as formation upper layer part 32, preferably uses and contains oxygen (O₂), nitrogen (N₂) and non-active gas gaseous mixture Body., can be with order that cross sectional shape is vertically changed in the case where lower layer part 31 is carbon nitrogen oxidation chromium (CrCON) layer containing carbon Carbon nitrogen oxidation chromium (CrCON) layer containing trace carbon is formed in the upper layer part 32 in addition to face side.In this case, make non- It is micro in active gases to contain hydrocarbon gas.As hydrocarbon gas, can enumerate：Methane, butane, propane etc..In nonactive gas When containing micro hydrocarbon gas in body, its content is preferably set to less than 15%, is further preferably set to less than 12%.Thickness side To the control that is distributed of composition can be carried out by the configuration of gas introduction port, method for supplying gas etc..Here, to sputter work( When the small condition of rate carries out film forming, the film of densification can be formed, is not likely to produce film defect.

Film defect is not likely to produce in order to which upper layer part 32 to be formed to the film of densification, the condition of sputtering power is preferably set to It is 3.0kW following.Reduction and productivity in view of film defect, are preferably set to more than 1.0kW and below 3.0kW by sputtering power, Further preferably it is set to more than 1.0kW and below 2.5kW.

Process more than, when pallet 301 is by near sputtering target material 334, by reactive sputtering, in lower layer part Given thickness and the upper layer part 32 (CrON layers, CrCON layers) being made up of the chromium compound containing chromium, nitrogen and oxygen are formed on 31.Need It is noted that in the case where upper layer part 32 is the carbon nitrogen oxidation chromium (CrCON) containing chromium, oxygen, nitrogen and carbon, make upper layer part 32 Face side have and be substantially free of the region of carbon.

Then, pallet 301 is moved to output room UL, is then shut off baffle plate 312, and vacuum exhaust, Ran Houxiang are carried out to room UL Atmosphere opening, substrate holder is taken out to the outside of sputter equipment 300.

The transparency carrier for foring photomask is taken out from substrate holder, carries out defect inspection, cleaning, manufacture as needed Photomask blank 100.

The photomask blank 100 manufactured in embodiment 1 is high for the adaptation of resist film, can suppress wet etching Liquid immerses the interface of resist film and photomask blank (antireflection layer), therefore mask pattern when can be formed photomask Cross sectional shape is vertically changed.In addition, antireflection layer 3 is formed by the film of densification, therefore, it is possible to suppress the generation of film defect, and can be with Possesses high resistance to chemical reagents.

The ＞ of ＜ embodiments 2

In embodiment 2, Fig. 3 that manufacturing process is shown in the form of main portion sectional view is used to display device Manufacture is illustrated with the manufacture method of photomask.

First, the photomask blank 100 of preparation is coated with and before forming resist, using the cleaning fluid containing sulfuric acid, (decoction cleans for cleaning before the decoctions such as ozone clean liquid carry out resist coating：Chemical Cleaning).Particularly, as Cleaned before resist coating, ozone clean liquid can be used to carry out ozone clean.Ozone clean removes the different of resist coated face Thing and pollutant.Although the ozone clean is effective for the foreign matter and pollutant of removing resist coated face, applying The research process that people completes the present invention obtain following opinion：In the case where using the resist without surfactant, Sometimes also there is the situation that the adaptation of resist is deteriorated and makes resist coating performance be deteriorated.Therefore, in existing photo blanks In the case of material, the adaptation deficiency with resist (resist for being free of surfactant), the cross sectional shape cone of pattern be present The hidden danger of shape, but according to the photomask blank of present embodiment, the problem of such can be suppressed.

Hereinafter, enumerate before ozone clean is coated with as resist and clean to illustrate, as cleaning device, cleaning side Method, it could alternatively be the decoction carried out using decoctions such as the cleaning fluids containing sulfuric acid and clean (Chemical Cleaning).

Representational ozone clean is to have used the rotary-cleaning of Ozone Water, but can also enter to be about to photomask blank 100 It is put into the bath cleaning cleaned in ozone clean liquid (Ozone Water) bath.Rotary-cleaning has cleaning suitable for monolithic processing The feature that the consumption of liquid is few and cleaning device is compacter, bath, which cleans to have, can clean multi-disc photomask blank 100 simultaneously Feature.For large-scale display device manufacture photomask blank, due to photomask blank and large-scale, therefore, from From the viewpoint of the consumption of cleaning fluid and the compactness of cleaning device, preferred pair large-scale display device manufacture photo blanks The ablution that material is handled using monolithic, particularly preferably uses rotary-cleaning method.

In the ozone clean based on rotary-cleaning method, first, ozone clean drop is added to and covered with the light of low speed rotation Near the rotating center section of mold base material 100, it is coated and is sprawled using rotation, ozone clean liquid is filled into photomask blank 100 Upper layer part 32 whole surface.Then, ozone supply cleaning fluid is until clean the end time, and make photomask blank 100 low Speed rotation, is persistently cleaned, and after scavenging period terminates, supplies pure water, ozone clean liquid is replaced into pure water, finally carried out Rotary drying.Ozone clean liquid is being filled to the whole of the upper layer part 32 of photomask blank 100 it should be noted that can also use Stop ozone clean drop behind individual surface and add the paddle ozone clean rotated with photomask blank.Make the low speed of photomask blank 100 The flow liquid formula rotary-cleaning method for rotating and flowing continuously through cleaning fluid is not susceptible to change with ozone concentration, also flowed with utilization The feature of mechanicalness cleaning performance caused by liquid, paddle ablution have the few feature of the consumption of ozone clean liquid.Rotation Turning cleaning method has above-mentioned feature, but due to ozone clean drop to be added to the pivot of photomask blank 100 first Portion, therefore easily by the cleaning impact of the concentric circles centered on rotating center section (cleaning damages).Therefore, easily with one heart Produce to round shape cleaning damage difference.Display device manufacture uses such as 1220mm × 1400mm so mostly with photomask blank The big blank of photomask blank size, the cleaning damage difference (distributional difference in damage surface) of its concentric circles has inclining for increase To.Therefore it is desirable, especially for, it is necessary to improve ozone clean patience for display device manufacture photomask blank.Need to illustrate If entering to be about to the pretreatment that pure water supplies to the surface of photomask blank 100 and soaks its surface in advance, then it is added dropwise Ozone clean liquid, then it can mitigate caused by ozone clean drop adds to the initial damage of photomask blank surfacing (first Secondary Shocks).

After being cleaned before the resist carried out using ozone clean the coating, then carry out in the upper of photomask blank 100 Resist patterns 4a Resist patterns formation process is formed in layer portion 32.

Specifically, in the Resist patterns formation process, first in the most surface layer as photomask blank 100 Resist film 4 (Fig. 3 (b)) is formed in upper layer part 32.Then, to the figure desired by the protracting circuit of resist film 4, pattern of pixels etc. Case.As the drawing light, the light that wavelength is 355nm, 365nm, 405nm, 413nm, 436nm and 442nm etc. can be generally used, Particularly laser.Can also be that the EB (Electron Beam) for having used electron beam draws.Then, will with given developer solution Resist film 4 develops, and forms Resist patterns 4a (Fig. 3 (c)).

Then, using Resist patterns 4a as mask, wet etching is carried out with photomask to mask pattern, forms photomask Pattern (shading layer pattern 2a and antireflection layer pattern 3a) (Fig. 3 (d)).Mask pattern photomask is by light shield layer 2, lower layer part 31 And upper layer part 32 is formed, in order to reduce operation quantity, wet etching is carried out preferably together.The reduction of operation quantity not only contributes to Improve disposal ability, simplify Etaching device, and be advantageous to improve defect quality.The photo blanks manufactured in embodiment 1 In material 100, all layers for forming the mask pattern photomask from light shield layer 2 to upper layer part 32 are formed by the material containing chromium, And it have adjusted the composition of constituent material so that relative to the etching speed of chromium etching solution along from the side of transparency carrier 1 towards transparent The film thickness direction increase of the side of substrate 1, therefore, even if carrying out wet etching together, the section of main part is also vertical, is not easy scheming Case bottom occurs end and elongates and be not likely to produce chromium etch residue.As chromium etching solution used herein, can specifically enumerate： Etching solution containing ammonium ceric nitrate and perchloric acid, the alkaline solution without cerium.

Then, Resist patterns 4a is removed using anticorrosive additive stripping liquid controlling, attrition process etc., is cleaned.As cleaning fluid, It can use for example：It is sulfuric acid, sulfuric acid/hydrogen peroxide (SPM), ammonia, ammonia/hydrogen peroxide (APM), OH free radicals rinse water, smelly Oxygen water etc..Then, pattern defect detection, defect correction etc. are suitably masked as needed.Thus, manufacture in transparency carrier 1 The upper photomask 200 with by shading layer pattern 2a, lower layer part pattern 31a and upper layer part pattern 32a the shading film figure formed.

In the manufacture method of above-mentioned photomask 200, resist film 4 is directly formd in upper layer part 32, but can also Etching mask is formed in upper layer part 32, then is formed on resist film 4.Resist patterns 4a is formed in aforementioned manners Afterwards, the etching is processed with mask with wet etching, then using the etching after processing by the use of mask as mask, to by shading The photomask that layer 2, lower layer part 31 and upper layer part 32 are formed carries out wet etching.Then, the etching mask after processing is removed.It is anti- Erosion agent pattern 4a can be removed immediately in processing etching with after mask, can also be removed after the wet etching of photomask.Losing Quarter with mask be there is high wet etching patience and improved with the adaptation of chromium oxide and the material that prevents wet etching solution from immersing In the case of, can be obtained with this method comprising upper layer part orthogonal cross-sectional shape shading film figure.As etching mask Material, can enumerate in silicon containing at least material of any one in metal, oxygen, nitrogen or carbon, for example, MoSi, SiO, SiON, SiC etc..

In addition, in the case where photomask blank is above-mentioned phase shift mask blank, multi-stage grey scale mask blank, using The method of stating is etched processing to functional membrane after foring shading film figure, and the functional membrane is formed at transparency carrier 1 and shading It is the phase of control exposure light and/or the film of transmissivity described in embodiment 1 between layer 2.In addition, needing to finely tune phase In the case of position, erosion obtained from being mixed in hydrofluoric acid aqueous solution using the diluted hydrofluoric acid aqueous solution or by the buffer solution of ammonium fluoride etc. Carve liquid and transparency carrier 1 is etched to desired depth.Then, Resist patterns 4a is removed, manufactures phase shifting mask.

The photomask 200 manufactured in embodiment 2 is high to the adaptation of resist film, can suppress wet etching solution immersion The interface of resist film and antireflection layer 3, therefore the cross sectional shape of shading film figure (mask pattern) can be made vertically to change.

It is in addition, high for the patience of the ozone clean of cleaning before being coated with as resist.Therefore, to mask pattern drawing light Reflectivity change it is small, the reflectivity to the light in photo blanks charge level is identical.Therefore, the mask pattern of formation CD deviations are small.In addition, also have mask pattern few with the film defect of photomask 2, the defects of generation in fabrication mask process Few feature.

The ＞ of ＜ embodiments 3

In embodiment 3, the manufacture method of display device is illustrated.

It is anti-firstly, for being formd on the substrate of display device in the manufacture method of the display device of embodiment 3 Lose agent film the substrate with resist film, by the photomask 200 obtained by the manufacture method illustrated in embodiment 2 with every The projection optical system of exposure device and such configuration opposed with forming the resist film on substrate is placed in exposure dress In the mask platform put.

Then, to the irradiation exposure light of photomask 200, it is exposed the anti-aging drug process of resist film.

Exposure light is, for example, more than 365nm and the light of below 550nm wave-length coverages, specifically, usually using wavelength The light of single wavelength such as the g rays of 365nm i rays, 405nm h rays and 436nm or include their complex light.

According to the manufacture method of the display device of the embodiment 3, obtained using the manufacture method illustrated in embodiment 2 Photomask manufacture display device.Therefore, fine pattern can be formed to high accuracy and low defect.Except the photo-mask process Beyond (exposure, developing procedure), by by the etching of machined membrane, dielectric film, the formation of conducting film, the importing of dopant, Or the various processes such as annealing, the display device of the fine that form desired electronic circuit can be manufactured with high finished product rate.

Embodiment

Hereinafter, for each embodiment, the present invention will be described in more detail referring to the drawings.It should be noted that each In embodiment, identical inscape uses identical symbol, and simplifies or the description thereof will be omitted.

(embodiment 1)

Fig. 3 is the accompanying drawing that can also be used in the explanation of embodiment 2, and it is to show to be used up by display device manufacture to cover Mold base material 100 makes the major part schematic cross-section of the process of display device manufacture photomask.

As shown in Fig. 3 (a), the photomask blank 100 of embodiment 1 includes transparency carrier 1, has and is mainly used in display device The antireflection layer 3 of the reflection of the light shield layer 2 and reduction mask pattern drawing light of the function of blocking exposure light of manufacture, shading Layer 2 forms mask pattern photomask together with antireflection layer 3.Light shield layer 2 is by chromium compound (the present embodiment containing chromium and nitrogen In be CrON) form, antireflection layer 3 is by two layers of the chromium compound of (upper layer part 32, lower layer part 31) containing chromium, oxygen and nitrogen (CrCON) form.

First, the details of the manufacture method to the photomask blank 100 and membrane structure illustrates.

((manufacture of photomask blank))

(((transparency carrier)))

Prepare the conjunction of 8092 sizes (about 800mm × 920mm) of the 1st interarea and the 2nd the two surfaces of interarea by polishing Into quartz glass substrate, as transparency carrier 1.Here, used thickness be 10mm substrate but it is also possible to be 8mm substrate. It can suitably carry out including rough polishing manufacturing procedure, precise polished manufacturing procedure, partial operation process and contact polishing work The polishing of sequence, so as to which flat and smooth main surface is made.

(((photomask)))

Carried out using large-scale type sputter equipment 300 (Fig. 2) in upright arrangement on transparency carrier 1 by light shield layer 2 and antireflection layer 3 The film forming of the mask pattern photomask of composition, the light shield layer 2 are made up of, institute chromium compound (being CrON in the present embodiment 1) Antireflection layer 3 is stated to be made up of two layers of (upper layer part 32, lower layer part 31) chromium compound (being CrCON in the present embodiment 1).

Next, the film build method of these films is illustrated.

First, carried by the main surface (surface of photomask to be formed) of the transparency carrier 1 towards downside and by transparency carrier 1 The pallet 301 for being placed in substrate holder (not shown) transports the input chamber LL of the type sputter equipment 300 in upright arrangement shown in Fig. 2.Here, The sputtering target material 331,332,333 and 334 comprising chromium (Cr) is configured with 1 sputtering chamber SP1, the 2nd sputtering chamber SP2.

Baffle plate 311 is opened, the pallet 301 for being placed with transparency carrier 1 is moved to the 1st sputtering chamber SP1 from input chamber LL, from Argon gas (Ar), nitrogen are imported with 331 corresponding gas introduction port of sputtering target material and with 332 corresponding gas introduction port of sputtering target material (N₂) and oxygen (O₂) mixed gas, to sputtering target material 332 apply 9kW sputtering power (sputtering target material 331 be 0kW), progress Reactive sputtering.It should be noted that in the present embodiment, from each gas introduction port corresponding with sputtering target material 331~334 The gas illustrated individually below is imported simultaneously.

On the flow of gas, Ar 70sccm, N₂For 15sccm, O₂It is 3sccm (with 331 corresponding gas of sputtering target material Introducing port, with 332 corresponding gas introduction port of sputtering target material it is the same terms).Now, pallet 301 is made with 400mm/ points Speed moves in the 1st sputtering chamber SP1.By the process, with about 80nm thickness on the main surface of transparency carrier 1 film forming CrON films as light shield layer 2.

Argon gas (Ar), nitrogen (N are imported from 333 corresponding gas introduction port of sputtering target material₂) and carbon dioxide (CO₂), apply 2.2kW sputtering power to sputtering target material 333, carry out reactive sputtering.On gas flow, argon gas is 60sccm, nitrogen 25sccm, carbon dioxide 17sccm.Now, pallet 301 is made to be moved with 400mm/ points of speed. By the reactive ion sputtering process, thickness about 20nm is formd on the about 80nm of the thickness as light shield layer 2 CrON films CrCON films (lower layer part 31).

Then, 12% methane (CH is mixed with from 334 corresponding introducing port of sputtering target material importing argon gas (Ar)₄) Mixed gas, nitrogen (N₂) and oxygen (O₂), apply 2.4kW sputtering power to sputtering target material 334, carry out reactive sputtering. On gas flow, the mixed gas of argon gas and methane is 60sccm, nitrogen 32sccm, oxygen 12sccm.Now, support is made Disk 301 is moved with 400mm/ points of speed.By the reactive ion sputtering process, in thickness about 20nm CrCON films (lower floor Portion 31) on form thickness about 20nm CrCON films (upper layer part 32).

Then, pallet 301 is moved to output room UL from the 2nd sputtering chamber SP2, be then shut off baffle plate 312, carry out vacuum row After gas, output room UL is reverted into atmospheric pressure state, substrate holder is taken out from sputter equipment 300.

Thus, obtained on synthetic quartz glass substrate formed with by CrON (light shield layer), CrCON (lower layer part), The photomask blank 100 for the photomask that CrCON (upper layer part) is formed.

The membrance casting condition of each film (each layer) described above is listed below.

Sputtering 1：Ar=70sccm, N₂=15sccm, power=0kW, pallet travelling speed=400mm/ point

Sputtering 2：Ar=70sccm, N₂=15sccm, power=9.0kW, pallet travelling speed=400mm/ point

Sputtering 3：Ar=60sccm, N₂=25sccm, CO₂=17sccm, power=2.2kW, pallet travelling speed= 400mm/ points

Sputtering 4：Ar/CH₄(12%)=60sccm, N₂=32sccm, O₂=12sccm, power=2.4kW, pallet transport Speed=400mm/ points

It should be noted that sputtering 1~3 gas supply from upstream side to target supply, sputter 4 gas supply under Side is swum to supply target.

For obtained photomask blank, the group composition of depth direction has been carried out using X-ray photoelectron spectroscopy (XPS) Analysis.It the results are shown in Fig. 4.

As shown in the drawing, the content of the chromium contained in antireflection layer is less than the content of the chromium contained in light shield layer, and subtracts The oxygen content contained in the upper layer part in reflecting layer is more than the oxygen content that lower layer part contains.(the content of the oxygen contained in antireflection layer More than the content of the oxygen contained in light shield layer, and the oxygen content contained in the upper layer part in antireflection layer be more than lower layer part in contain Some oxygen contents.)

In addition, the face side in upper layer part (except autoxidation and produces the most surface layer of pollution (away from case depth about Beyond 2nm)) the region A for being substantially free of carbon is formed with about 6.5nm thickness, region A oxygen continuously increases towards most surface Add, on the contrary, nitrogen continuously reduces.

Fig. 5 is illustrated that based on XPS analysis result to figure obtained from the mapping of the ratio between nitrogen and oxygen.As shown in the drawing, region A Middle oxygen is more than 5 relative to the maximum of the ratio (O/N) of nitrogen, and minimum value is more than 2.8.

It should be noted that " being substantially free of carbon " refers to below XPS carbon detectable limit.

Determined using flatness measure device before forming photomask (light shield layer 2 and antireflection layer 3) on transparency carrier 1 Flatness variable quantity afterwards, result are 5 μm, it is thus identified that the membrane stress of photomask is low.It is believed that this is due to tensile stress, compression Caused by the stress neutralization effect that stress is formed, the tensile stress is due to light shield layer for the chromium nitride institute containing micro amount of oxygen The material of composition and it is caused, the compression stress, which is due to antireflection layer, is more than the chromium compound institute structure of light shield layer for oxygen content Into material and it is caused.

((manufacture of photomask))

Next, photomask 200 is manufactured using photomask blank 100.

First, ozone clean has been carried out to ready photomask blank 100 using ozone clean liquid.

The ozone clean proceeds as described below.First, ozone clean drop is added to the photomask blank 100 of low speed rotation Rotating center section near, be coated and sprawled using rotation, ozone clean liquid is filled to the upper layer part 32 of photomask blank 100 Whole surface.Then, sustainable supply cleaning fluid is up to the cleaning end time, while makes the low speed rotation of photomask blank 100, holds It is continuous to be cleaned, after scavenging period terminates, pure water is supplied, ozone clean liquid is replaced into pure water, it is dry finally to have carried out rotation It is dry.

(Fig. 3 (a)) has carried out defect inspection at this stage.Defect inspection is carried out to 790mm × 910mm region, dark In room to film surface irradiate high intensity light, observe by the naked eye to 10 μm with the defects of checked.As a result, the light The defects of mask blank 100 checks quantity is 0.

The change of the reflectivity (wavelength 436nm) after ozone clean is determined, its result is 0.06%, it is thus identified that ozone is clear It is high to wash patience.

Then, as shown in Fig. 3 (b), using the photoresist without surfactant on the upper strata of photomask blank 100 Thickness 525nm resist film 4 is formd in portion 32.Then, using laser plotter to the protracting circuit pattern of resist film 4 Deng desired pattern, then developed, rinsed, so as to form given Resist patterns 4a (Fig. 3 (c)).Here, use The wavelength of drawing light of laser plotter be 413nm.Then, using Resist patterns 4a as mask, wet etching pair is passed through Photomask integratedly carries out pattern and formed, and forms shading film figure (Fig. 3 (d)), the photomask by transparency carrier 1 according to The CrON layers (light shield layer 2) of secondary formation, CrCON layers (lower layer part 31), CrCON layers (upper layer part 32) 3 layers of composition of this total.Cause This, shading film figure includes：The shading layer pattern 2a that is made up of CrON, by the CrCON lower layer part pattern 31a formed and by The upper layer part pattern 32a that CrCON is formed (this 2 layers are antireflection layer pattern 3a).Here, as wet etching, used and contained The chromium etching solution of ammonium ceric nitrate and perchloric acid.

Using the sample made according to same operation up to process above, using SEM to remaining The cross sectional shape of shading film figure in the state of Resist patterns 4a is shot, and Fig. 6 is the photo that shooting obtains.

As shown in the drawing, obtained extremely close to the shading film figure of vertical cross sectional shape.

Then, Resist patterns (Fig. 3 (e)) is peeled off, has obtained forming wired and space pattern (L/ on transparency carrier 1 S) the photomask 200 for the shading film figure for being 2 μm.

The SIR8000 manufactured using Seiko Instruments Nanotechnology companies determines the photomask The dimensional discrepancy (CD deviations/CD uniformities) of mask pattern.In the measure of CD deviations, for the fringe region except substrate with Outer 880mm × 910mm region, it is determined at 5 × 5 position.In following embodiment and comparative example, CD is uniform The measure of property has used identical device and identical evaluation method.

The result is that CD uniformities are 0.078 μm.The situation of comparative example is described below, but the CD uniformities of comparative example are 0.15 μm, the CD of embodiment 1 has good uniformity.

((manufacture of display device))

The photomask 200 made in the embodiment 1 is installed on to the mask platform of exposure device, to the substrate in display device On the sample formed with resist film carried out pattern exposure.Then, by developing to the resist film after the exposure, Resist patterns is formd on display device substrate.As exposure light, i rays, the 405nm h for including wavelength 365nm have been used The wavelength of ray and 436nm g rays is more than 300nm and below 500nm light.

The photomask 200 made in embodiment 1 is expressed as 0.078 μm with CD uniformities, and mask pattern dimensional accuracy is high, right It is also low in the reflectivity of above-mentioned exposure light, and quantity is also 0 the defects of the photomask blank stage, defect is few, therefore shows dress The precision for putting the transfer pattern of the Resist patterns on substrate is also high and defect is few.

The Resist patterns is transferred on machined membrane by etching, and by dielectric film, conducting film formation, mix The various processes such as miscellaneous dose of importing or annealing, the display device of the fine with expected characteristics can be manufactured with high finished product rate.

(embodiment 2)

For the photomask blank of embodiment 2, it is the chromium nitride (CrN) for being substantially free of oxygen to make light shield layer 2, and is adjusted The whole thickness of light shield layer 2 and antireflection layer 3 (lower layer part 31, upper layer part 32), in addition, makes similarly to Example 1 Photomask blank.

In the film forming of the light shield layer 2 of embodiment 2, it is 70sccm, N that the gas flow of embodiment 1 is set into Ar₂For 15sccm, the sputtering power using the thickness of the CrN films of light shield layer 2 as about 80nm have carried out film forming.

In addition, in the upper layer part of antireflection layer 3 and the film forming of lower layer part, gas flow same as Example 1 is set to, Using the thickness of the CrCON films of lower layer part 31 as about 20nm sputtering power, using the thickness of the CrCON films of upper layer part 32 as about 20nm Sputtering power carried out film forming.

XPS analysis are carried out for obtained photomask blank, the result is that not detecting oxygen in light shield layer 2, it is thus identified that It is made up of chromium compound, the chromium compound is the chromium nitride formed by chromium and nitrogen.

Then, for obtained photomask blank, membrane stress, ozone clean patience are have rated similarly to Example 1.

Before and after determining film forming photomask (light shield layer 2 and antireflection layer 3) to transparency carrier 1 using flatness analyzer Flatness variable quantity, it is as a result 4 μm, it is thus identified that the membrane stress of photomask is low.It is considered that this is due to tensile stress, compresses and answer Caused by stress neutralization effect caused by power, the tensile stress is due to that light shield layer is produced by the material that chromium nitride is formed Raw, the compression stress is due to that antireflection layer is produced by oxygen content more than the material that the chromium compound of light shield layer is formed 's.

Change to the reflectivity (wavelength 436nm) before and after ozone clean is determined, and is as a result similarly to Example 1 0.06%, it is thus identified that ozone clean patience is high.

(embodiment 3)

The photomask blank of embodiment 3 is with foring phase shift film (phase between photomask in transparency carrier 1 and mask pattern Position adjustment layer) photomask blank, that is, so-called phase shift mask blank, the phase shift film is the transmissivity of adjustment exposure light And the functional membrane of phase transition amount.It should be noted that the mask pattern being formed on phase shift film is and embodiment 1 with photomask Identical photomask, the description thereof will be omitted.

Using large-scale type sputter equipment in upright arrangement, made of the synthetic quartz glass substrate by size same as Example 1 The film forming of the phase shift film by the MoSiN two membranes formed has been carried out on transparency carrier 1.In the film forming of phase shift film, by the 1st sputtering Room SP1, the 2nd sputtering chamber SP2 sputtering target material replace with the sputtering target material 331,333 being made up of molybdenum silicide (MoSi) respectively, press The film forming of phase shift film has been carried out according to following membrance casting condition.

Sputtering 1：Ar=50sccm, N₂=90sccm, power=8.0kW, pallet travelling speed=400mm/ point

Sputtering 3：Ar=50sccm, N₂=90sccm, power=8.0kW, pallet send speed=400mm/ points

According to above-mentioned membrance casting condition, in the sputtering 1, on transparency carrier 1 film forming by thickness 55nm nitrogen molybdenum silicide The 1st layer of phase shift film that film (MoSiN) is formed, in sputtering 3, film forming is formed by thickness 55nm nitrogen molybdenum silicide film (MoSiN) The 2nd layer of phase shift film, the total film thickness 110nm being made up of two layers of nitrogen molybdenum silicide film (MoSiN) phase is formd on transparency carrier 1 Move film.

Using the MPM-100 of Lasertec companies manufacture to foring basal lamina determination transmissivity, the phase of the phase shift film Difference.In transmissivity, the measure of phase difference, it is determined using the model substrate of 6025 sizes made simultaneously.Its result It is that transmissivity is 5.5% (wavelength：365nm), phase difference is 180 ° of (wavelength：365nm).

Next, mask pattern same as Example 1 photomask (light shield layer 2 and antireflective are carried out on phase shift film The film forming of layer 3), has manufactured phase shift mask blank.

Phase shift mask blank obtained above is carried out in evaluation method same as Example 1 and under the same conditions Evaluation.The chromium content of mask pattern photomask 5, containing oxygen distribution, it is nitrogenous distribution it is identical.

Then, phase shifting mask has been manufactured using the phase shift mask blank.

First, using ozone clean liquid to have carried out ozone to ready phase shift mask blank similarly to Example 1 clear Wash.

Then, thickness 525nm resist is formd on photomask using the photoresist without surfactant Film 4.Then, using laser plotter to the pattern desired by the protracting circuit pattern of resist film 4 etc., then developed, rushed Wash, so as to form given Resist patterns 4a.Then, using Resist patterns as mask, by wet etching, using containing There is the chromium etching solution of ammonium ceric nitrate and perchloric acid to carry out pattern to the photomask to be formed, form prepared shading film figure.

Then, Resist patterns is not removed, using Resist patterns and shading film figure as mask, by wet etching, Using with the addition of the oxidants such as hydrogen peroxide, nitric acid, sulfuric acid in the fluorochemicals such as hydrofluoric acid, fluosilicic acid, hydrofluoric acid ammonium and Obtained etching solution, pattern is carried out to phase shift film and formed, has formd phase shift film figure.

Then, Resist patterns is not removed, above-mentioned chromium etching solution is reused and preparation shading film figure is lost again Carve, the central portion on phase shift film figure forms the shading film figure with desired pattern line-width.

Finally, Resist patterns is peeled off, has obtained phase shifting mask, the phase shifting mask forms line on transparency carrier 1 It is 2 μm of phase shift film figure with space pattern, and shading film figure is formd on the central portion of phase shift film figure.

Determining, have rated the dimensional homogeneity of the phase shift film figure of the phase shifting mask similarly to Example 1, (CD is uniform Property), result is that CD uniformities are 0.08 μm.The phase shifting mask has the sufficiently small high-precision phase shift film figure of CD uniformities.Cause This, can be similarly to Example 1 with the display device of fine of the high finished product rate manufacture with expected characteristics.

(comparative example)

The membrance casting condition of comparative example is shown in following.

Sputtering 1：Ar=65sccm, N₂=15sccm, power=1.5kW, pallet travelling speed=400mm/ point

Sputtering 2：Ar/CH₄(4.9%)=31sccm, power=8.5kW, pallet travelling speed=400mm/ point

Sputtering 3：Ar=34.8sccm, N₂=32.2sccm, CO₂=4.5sccm, power=1.74kW, pallet travelling speed =400mm/ points

Sputtering 4：Ar=34.8sccm, N₂=32.2sccm, CO₂=4.5sccm, power=1.74kW, pallet travelling speed =400mm/ points

It should be noted that the gas supply of sputtering 1~4 supplies from upstream side to whole targets.

Thus obtained photomask blank possesses CrN light shield layer and antireflection layer, the antireflective on the transparent substrate It is CrCON upper layer part and 2 Rotating fields of lower layer part that layer, which is,.

For the photomask blank of obtained comparative example, depth direction has been carried out using X-ray photoelectron spectroscopy (XPS) Composition analysis.It the results are shown in Fig. 7.

As shown in the drawing, although the content of the oxygen contained in antireflection layer is more than the content of the oxygen contained in light shield layer, The oxygen content contained by portion substantially with lower layer part is phase same level to antireflection layer at the middle and upper levels.

In addition, the face side in upper layer part is not present and is substantially free of the region of carbon, the containing ratio of nitrogen and oxygen substantially without Significant change.

Next, for obtained photomask blank, membrane stress, ozone clean patience are have rated similarly to Example 1.

Before and after determining film forming photomask (light shield layer 2 and antireflection layer 3) to transparency carrier 1 using flatness analyzer Flatness variable quantity, it is as a result 7.5 μm.In addition, the change of the reflectivity (wavelength 436nm) before and after determining ozone clean, knot Fruit is 2.11%.Compared with embodiment 1,2, membrane stress and ozone clean patience are deteriorated.

The photomask blank manufactured using the method by comparative example 1, and formed and hidden using method same as Example 1 Light film figure, the cross sectional shape by SEM to the shading film figure in the state of remaining Resist patterns 4a Shot, Fig. 8 is the photo that shooting obtains.

As shown in the drawing, cross sectional shape is the taper for foring very long end.It is considered that the reason is that because anti- The problem of losing adaptation of the agent (resist for being free of surfactant) with antireflection layer etc., wet etching solution is immersed in resist The interface of film and antireflection layer, causes heavy corrosion.

In addition, the CD uniformities of the photomask manufactured by method same as Example 1 are 0.15 μm.

As known from the above, in embodiment and comparative example, (possess on the transparent substrate although basic membrane structure is identical CrON or CrN light shield layer and antireflection layer, it is CrOCN upper layer part and two layers of knot of lower layer part that the antireflection layer, which is, Structure), but for the photomask blank of comparative example, in the formation of shading film figure, its cross sectional shape is very big taper.

On the other hand, on the photomask blank of embodiments of the invention possesses by using the manufacture method of described above Bright structure is stated, in the formation of shading film figure its cross sectional shape can be made vertically to change.

In addition, using the photomask blank of embodiment, antireflection layer 3 is by upper layer part 32 and lower layer part 31 this double-layer structure shape Into be compared relative to the content of respective oxygen and nitrogen understands that lower layer part 31 is rich nitrogen, and upper layer part 32 is oxygen-enriched.By This, as membrane stress, produces tensile stress, compression stress is produced in upper layer part 32 in lower layer part 31, membrane stress is cancelled out each other, because This can reduce the stress overall as film.

Claims

1. a kind of photomask blank, it has made of the material substantially transparent to exposure light transparency carrier, described transparent The antireflection layer on light shield layer and the light shield layer on substrate, wherein,

The light shield layer is formed by the chromium compound containing chromium and nitrogen,

The antireflection layer is formed by the chromium compound containing chromium, nitrogen and oxygen,

The content of the chromium contained in the antireflection layer is less than the content of the chromium contained in the light shield layer,

The antireflection layer is the stack membrane that lamination multilayer forms, the oxygen contained by the upper layer part of the face side of the antireflection layer Oxygen content of the content contained by more than the lower layer part of the light shield layer side of the antireflection layer, has in the face side of the upper layer part Be substantially free of the region of carbon, in the region, oxygen continuously increases towards most surface, and oxygen relative to nitrogen ratio O/N most Big value is more than 5.

2. photomask blank according to claim 1, wherein, the oxygen relative to the ratio O/N of nitrogen minimum value for 2 with On.

3. photomask blank according to claim 1, wherein, have adjustment saturating between the transparency carrier and light shield layer Penetrate the transmissivity adjustment layer of rate.

4. photomask blank according to claim 3, wherein, the transmissivity adjustment layer includes to be had to the light shield layer The material of etching selectivity.

5. photomask blank according to claim 1, wherein, there is adjustment phase between the transparency carrier and light shield layer The phase adjustment layer of potential difference.

6. photomask blank according to claim 5, wherein, the phase adjustment layer includes has erosion to the light shield layer Carve the material of selectivity.

7. according to photomask blank according to any one of claims 1 to 6, wherein, formed with anti-on the antireflection layer Lose oxidant layer.

8. photomask blank according to claim 7, wherein, the resist layer is coated with anti-without surfactant Lose agent.

9. a kind of manufacture method of photomask blank, it is the manufacture of photomask blank according to any one of claims 1 to 8 Method,

This method includes：

Prepare the transparency carrier process,

Formed on the main surface of the transparency carrier light shield layer process and

The process that the antireflection layer is formed on the light shield layer,

This method also includes：

Comprising carbon dioxide, nitrogenous gas mixed gas atmosphere in institute formed by using the sputtering of chromium target The process for stating the lower layer part of antireflection layer,

Comprising oxygen-containing gas, nitrogenous gas mixed gas atmosphere in form by using the sputtering of chromium target described subtract The process of the upper layer part in reflecting layer.

10. there is following process to manufacture photomask for a kind of manufacture method of photomask, this method：

Usage right requirement 1~6 any one of photomask blank or pass through the manufacture method described in claim 9 The photomask blank of manufacture, the process that resist layer is formed on the photomask blank；

The process of pattern desired by being drawn to the resist layer；

Developed, the process that Resist patterns is formed on the photomask blank；And

The light shield layer and the antireflection layer are etched based on the Resist patterns, so as to form the process of pattern.

11. a kind of manufacture method of photomask, the photomask blank described in this method usage right requirement 7 or 8, and with following Process manufactures photomask：

The process of pattern desired by being drawn to the resist layer；

12. the manufacture method of the photomask according to claim 10 or 11, wherein, the resist layer is coated with without table The resist of face activating agent.

13. a kind of manufacture method of display device, this method include：

Exposure process, the photomask manufactured by the manufacture method of the photomask any one of claim 10~12 is carried The mask platform of exposure device is placed in, the transfer that will be formed on the photomask is transferred to pattern exposure is formed at display device Resist on substrate.