CN102213784A - Manufacturing method for dynamically-stamped reflective optical grating - Google Patents

Abstract

The invention discloses a manufacturing method for a dynamically-stamped reflective optical grating. In specific to the problems that the manufacturing cost of the conventional photoetching process increases sharply along with the increase of processing accuracy, the processing speed of the conventional stamping process cannot meet the practical requirement and the processing accuracy is required to be increased, a large-measuring-range optical grating manufacturing process which combines continuous roller stamping with an scoring technology is designed and manufactured reasonably with the method. In the method, a roller stamped optical grating mold is manufactured by using electron beams, and parallel circular projecting microstructures are formed on the surface of the mold. A substrate has a three-layer structure and consists of a metal layer, a polymer layer and a cushion layer from top to bottom. In the machining process, large-measuring-range optical gratings are manufactured in batch under the actions of the autorotation of a stamping roller and sliding of the stamping roller relative to the substrate.

Description

The method for making of dynamics impression reflective gratings

Technical field

The invention belongs to technical field of micro-nano manufacture, relate to a kind of novel manufacturing method of reflective gratings.

Background technology

The high precision displacement measuring technique is precision machined basis, and the displacement measurement precision has determined whole manufacturing manufacturing accuracy.Along with accurate manufacturing technology constantly develops, the raising of processed object precision requires displacement measuring instrument to have high precision, high resolving power, high reliability, wide range, small size and characteristics cheaply.In modern industrial technology fields such as microelectronics, superfinishing, also more and more higher to the accurate displacement Testing requirement.Grating has that measuring basis is fixed, not affected by environment, less demanding to the light source frequency stabilization, advantage that cost is low, has been widely used in that accurate displacement is measured, measurement of angle.Adopt in a large number in fields such as digital control processing, microelectronics.Along with the continuous progress of micro-nano process technology, the operation wavelength of grating develops into sub-micron even nanoscale from micron order, and the method for making that adopts comprises holographic lithography, X ray and beamwriter lithography at present.The holographic lithography system is very expensive, complicated, the photoetching process condition harshness of preparation nano-pattern; The area that X ray and beamwriter lithography are made is little, cost is high, fabrication cycle is longer.Nano impression is a kind of high resolving power, high controllability, arbitrary graphic clone method cheaply.The requirement of nanoscale grating and channel structure has been promoted the development of nanometer embossing, yet, traditional press-down type nano-imprint process can't satisfy the demand to output in actual production at present, roll-in seal technology is as a kind of new technique in nano impression field, can improve output to a certain extent, but can there be slit areas in the swing circle of roller platen in process, destroys the figure continuity, is difficult to increase substantially the process velocity of wide range grating.

At common process in the limitation aspect grating pattern continuity, production efficiency and the heating-up temperature, the present invention adopts a kind of dynamics roll-in seal technology of rolling and combining with the delineation shaping, nano impression is combined with cutter delineation technology, can realize the high speed, continuously shaped of wide range grating, produce grating in batches, enhance productivity.And can in substrate, realize the high fidelity replica of figure, prepare high-quality, wide range reflective gratings.

Summary of the invention

The objective of the invention is to overcome existing nano-imprint process makes in the wide range reflective gratings process, production efficiency is low, the pattern poor continuity, because template and difficulties such as substrate Continuous Contact friction effect machining precision, template life-span and crudy, provide a kind of dynamics to impress the method for making of reflective gratings.This method not only can realize the batch machining of wide range grating, enhances productivity, and can greatly prolong the serviceable life of mould.The continuity that keeps pattern.For achieving the above object, the present invention realizes by the following technical solutions.

Technical scheme of the present invention is achieved in that and comprises the following steps:

1) uses electronic beam method, at first plating Cr or Pt layer on template, spin coating one deck electron beam adhesive is as resist again, use the electron beam lithography resist then, again with resist as mask resist figure transfer on Cr or Pt layer, then this template is placed on etching template base material in the reactive ion etching machine, Cr that it is surperficial or Pt layer are as protective seam, use wet etching to remove the Cr or the Pt of template substrate surface at last, form the template that the surface has microstructure;

2) template is aimed at substrate, template is heated, when roller platen rotates, the circular cutter of template surface moves along the substrate surface direction vertical with the roller platen central axis, the rotation of cutter combines with the slip that substrate produces, technological process was divided into for 4 steps successively, the first step, and template contacts for the first time with the base material that will be stamped; Second step, template is carried out spot heating, heating region concentrates on the circular cutter microstructure in roller platen surface, temperature is controlled between 100 ℃-150 ℃, the deliquescing of also being heated of the base material of contact site, along with the rotation and the slip of template Roller cutter, the polymkeric substance institute applied pressure that is impressed is increased gradually, and reach stationary value; In the 3rd step, the cutter sharp edges is exerted pressure to the metal of substrate and is made it to produce plastic yield, when template slides forward, forms the grating raceway groove in substrate; In the 4th step, after the template process, polymkeric substance produces recovery of elasticity, and how much final patterns of decision grating raceway groove.

Characteristics of the present invention are:

Different with conventional nano-imprint process is, in the dynamics moulding process, the microstructure of template (Roller cutter) is delineated base metal, in the delineation process, each part of the little cutter of circumference all participates in the moulding of optical grating construction, avoid the wearing and tearing and the distortion that produce in the single contact site delineation process in the processing technology in the past, fully guaranteed the serviceable life of mould.

Description of drawings

(position 1 among the figure: roller platen in order to use roll-in die tool and substrate contact process synoptic diagram for Fig. 1; 2: Roller cutter; 3: metal level; 4: polymeric layer; 5: bed course; 6: heating or UV zone; 7: the plastically deforming area; 8: the recovery of elasticity district.

Fig. 2 is mould and substrate contact site spot heating synoptic diagram;

Fig. 3 is a grating forming process synoptic diagram;

Embodiment

The present invention is described in further detail below in conjunction with accompanying drawing.

As Fig. 1, the impression block surface of the present invention's design has circular cutter array, is arranged in parallel between each Roller cutter.

For the roller platen that guarantees to have the cutter microstructure under setting pressure, realize the controllability of aximal deformation value, should select the lower polymeric material of deformation modulus.

Base material will have sufficiently high toughness, influences process to avoid template to cause substrate fragmentation or generation residual pieces to accumulate in the process of delineating.

Basic functional principle of the present invention is: in the roller platen rotation process, the template surface Roller cutter contacts (as Fig. 1) with substrate.Template is heated to 100 ℃-150 ℃, because the contact area of template and substrate is very little, substrate heats up very fast, and only is confined to the contact site near zone, can not influence other zones.When roller platen rotates, substrate along with the opposite direction of tangent place point of contact direction of motion, with the speed v motion, make the Roller cutter of die surface when self rotates, and sliding process arranged between the substrate.The protruding circular ring that is parallel to each other depicts the optical grating construction that many roads are parallel to each other in substrate, as shown in Figure 3 as " cutter ".Spot heating makes polymkeric substance softening rapidly, for the high-speed mobile of template provides guarantee, has greatly improved production efficiency.Template with circular cutter has guaranteed that mould material can not appear at the excessive use of free of discontinuities in the single roll-in seal process because a certain position and cause wearing and tearing and the performance reduction in the forming process.In whole moulding process, metal level is in the upper strata of the polymer film that is impressed all the time, is not removed.

(1) prepares impression formboard with electron beam, the annulus projection micro structured pattern that is designed in advance at masterplate;

(2) be coated with polymeric layer in smooth layer on surface of metal shop, lay one deck bed course at polymer surfaces subsequently.

(3) technology that adopts the dynamics impression to combine with delineation technology makes template contact with substrate, and the circular protruding microstructure on the template is when self rotates, with sliding type delineation substrate.

What step (1) was used is the roll-in die plate, uses silicon and hard metal as the template base material.

Reticle surface is coated with very thin one deck Cr or Pt, to guarantee micro-structure surface hardness and anti-wear performance.Die plate pattern is to be the center of circle with roller platen right cylinder xsect and roller platen central axis intersection point, is positioned at a series of annulus of each xsect.Be parallel to each other between each annulus.The wide 100nm-100um of annulus, interior external diameter difference 5-8um, the donut cutter cycle is 200nm-200um.

The metal that base material is selected for use in the step (2) must have sufficiently high toughness, in order to avoid produce fragment in the template delineation process.Polymkeric substance will have low modulus, so that produce due deflection under given applied stress.

Template was carried out preheating earlier before the delineation microstructure, temperature makes base material softening at 100 ℃-150 ℃, is beneficial to delineation and carries out smoothly.

The grating cycle is 200nm-200um, and groove width 100nm-100um highly is 5um-8um, and length is 20cm.Section configuration by the annulus center of circle can be square, rectangle, trapezoidal, rhombus or hexagon and other irregular figures etc., designs and makes according to the shape of grating.

The specific implementation process that this reflective gratings dynamics impression is made is as follows:

(1) preparation of impression block.Use electronic beam method, at first plating Cr or Pt layer on template, spin coating one deck electron beam adhesive is used the electron beam lithography resist then as resist again, again with resist as mask resist figure transfer on Cr or Pt layer.Then this template is placed on etching template base material in the reactive ion etching machine, Cr that it is surperficial or Pt layer use wet etching to remove the Cr or the Pt of template substrate surface as protective seam at last, form the template that the surface has microstructure;

(2) template is aimed at substrate, to the template heating, as shown in Figure 2, when roller platen rotates, the circular cutter of template surface moves along the substrate surface direction vertical with the roller platen central axis, and the rotation of cutter combines with the slip that substrate produces, and technological process was divided into for 4 steps successively.The first step, template contacts (Fig. 1) for the first time with the base material that will be stamped; Second step, template is carried out spot heating (Fig. 2), heating region concentrates on the circular cutter microstructure in roller platen surface, and temperature is controlled between 100 ℃-150 ℃, the deliquescing of also being heated of the base material of contact site.Along with the rotation and the slip of template Roller cutter, the polymkeric substance institute applied pressure that is impressed is increased gradually, and reach a stationary value; The 3rd one, the cutter sharp edges has applied enough big pressure to the metal of substrate and has made it to produce plastic yield (zone 1).When template slides forward, form the grating raceway groove in substrate; In the 4th step, after the template process, polymkeric substance produces recovery of elasticity (zone 2) to a certain extent, and how much final patterns of decision grating raceway groove.

The present invention adopts dynamics to impress the mode that combines with delineation technology, can improve the production efficiency of a large amount of degree gratings, realizes producing in batches, solves the problem of manufacturing in batches, and cost is reduced greatly.

Claims (1)

1. the method for making of dynamics impression reflective gratings is characterized in that, comprises the following steps:

1) uses electronic beam method, at first plating Cr or Pt layer on template, spin coating one deck electron beam adhesive is as resist again, use the electron beam lithography resist then, again with resist as mask resist figure transfer on Cr or Pt layer, then this template is placed on etching template base material in the reactive ion etching machine, Cr that it is surperficial or Pt layer are as protective seam, use wet etching to remove the Cr or the Pt of template substrate surface at last, form the template that the surface has microstructure;

2) template is aimed at substrate, template is heated, when roller platen rotates, the circular cutter of template surface moves along the substrate surface direction vertical with the roller platen central axis, the rotation of cutter combines with the slip that substrate produces, technological process was divided into for 4 steps successively, the first step, and template contacts for the first time with the base material that will be stamped; Second step, template is carried out spot heating, heating region concentrates on the circular cutter microstructure in roller platen surface, temperature is controlled between 100 ℃-150 ℃, the deliquescing of also being heated of the base material of contact site, along with the rotation and the slip of template Roller cutter, the polymkeric substance institute applied pressure that is impressed is increased gradually, and reach stationary value; In the 3rd step, the cutter sharp edges is exerted pressure to the metal of substrate and is made it to produce plastic yield, when template slides forward, forms the grating raceway groove in substrate; In the 4th step, after the template process, polymkeric substance produces recovery of elasticity, and how much final patterns of decision grating raceway groove.

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