TWI271792B - Laser-annealed process photomask and method for forming polysilicon film layer by laser annealing - Google Patents

Abstract

The present invention provides a laser-annealed process photomask which includes a completely transparent region, a completely shielded region; and a partially transparent region, wherein the completely transparent region is surrounded by the completely shielded region, and the partial transparent region is distributed in the completely transparent region in order to alter the energy density distribution of the laser in the completely transparent region, thereby convert an amorphous material into a polysilicon material. The present invention also provides a method for forming a polysilicon film layer by using laser annealing in order to form a polysilicon film layer having non-continuous linear grain boundaries.

Description

1271792 V. INSTRUCTION DESCRIPTION OF THE INVENTION (1) Technical Field of the Invention The present invention relates to a laser anneal process reticle, and more particularly to a sequentia 1 1 atera 1 Solidif ication ; SLS ) Process mask used in the process of low temperature polysilicon process (LTPS process). [Prior Art] A thin film transistor is an active element commonly used in an active array type flat panel display, and is generally used to drive an active liquid crystal display (active matrix type liquid crystal display) or an active organic electroluminescent display (active matrix type). Organk light-emitting display ) and other devices. The semiconductor semiconductor in the thin film transistor can be divided into a p〇ly-silicon film and an amorphous silicon (a-Si:H) film. j Amorphous germanium film, although it has a low process temperature and is prepared by vapor deposition, is suitable for a large production, because of the mature process technology, resulting in high yield, etc., the conductive property of my stone is good, ★ with polycrystalline stone The film life of the film is 日 〃 〃 较 较 较 较 较 较 较 较 较 较 电 电 电 电 电 电 电 电 电 电 电 电 电 电 电 电 电 电 电 电 电 电 电 电 电 电 电 电 电 电 电 电 电 电 电Has gradually replaced the amorphous germanium film. _ There are three general methods for manufacturing polycrystalline germanium films. The first = stacking step is directly deposited, the second is to form an amorphous germanium film. 1 It is crystallized into a polycrystalline germanium film by thermal energy, and the third is formed first.

〇773-l〇4〇7TW(Nl); P92〇6〇; amy.ptd Page 5 1271792 V. Description of the invention (2) After the spar film, the laser is crystallized into a polycrystalline germanium film. However, the above method has the following disadvantages. The first method has the disadvantage that a polycrystalline ruthenium film which is thick enough to form a large crystal grain must be deposited, and the surface uniformity is poor, and the required process temperature is as high as 6 〇〇. Although the second method can produce a thin and uniform polycrystalline germanium film, the crystallization step requires a temperature of up to 600 degrees, a high thermal budget, and a long time required to affect the yield. The third method has a low process temperature, and the conventional method converts amorphous germanium into polycrystalline stone by excimer laser annealing (ELA), but its scanning speed is about 0. 2 mm/sec, the energy is about 37 0 mJ/cm2, not only the yield is low, but also limited by the energy of the big cockroach, the mouth A 7 Ganzi, and the mouth 曰曰 月 ^ 吊 吊 吊 吊 吊 吊 吊 吊The purpose of recrystallizing the entire layer of amorphous germanium into a multi-stone is not achieved. Continuous side-curing (SLS) laser annealing using a fast scanning speed (3 〇^ m / sec) and high laser energy (600 mj/cm2) converts non-sa stone into polycrystalline stone, Then you can solve the above problem. Continuous side solidification (SLS) is a technique in which the interface between the liquid phase and the solid phase is grown in the vertical direction, so that the tantalum film crystallizes into larger tantalum grains. And by controlling the laser beam and the radiation range, the germanium grains will grow laterally to a predetermined length. Month b. In the process of crystallizing the amorphous austenite layer into a polycrystalline stone layer by SLS, in the case of lateral crystal growth, the particles of the polycrystalline crucible will be pushed against each other to form an arrangement.

The order of the protrusion, you, 1, J, ^ 1 ^ one makes the roughness (roughness). Fig. 1 is a view showing the channel direction of the thin film transistor 41 prepared by using the above-mentioned 曰 纠 41 correction 1, sound seven a-立 I. As shown in Fig. ^., the corpse is not, the brother of a row of thin film Ray #杂41 channel area (as shown in the arrow, 曰 _ only) does include a 矽 grain boundary

1271792 V. Inventive Note (3) 3 2, but the channel region of the thin film transistor 4 1 of the second row (shown by the arrow in the figure) does not pass through any grain boundary 3 2, resulting in two thin film transistors The electrical properties of 4 1 are inconsistent. Therefore, such an arrangement of ordered protrusions (i.e., numeral 3 2) may result in poor electrical conductivity of the electron hole channel region, such as a bump in the drain current-gate voltage curve (Id~Vg curve). ), as shown in Fig. 2, where curve A is an abnormal curve that produces a bulge, and curve B is a normal curve. In view of the above, it is an object of the present invention to provide a method of laser annealing. When the amorphous film layer is crystallized into a polycrystalline film, the crystal grain boundary of the polycrystalline system does not form a continuous linear protrusion. Therefore, in the present invention, by providing a photomask for performing a laser annealing process, when the amorphous film layer is crystallized into a polycrystalline film, the crystal grain boundaries of the polycrystalline system do not form a continuous linear protrusion. The invention provides a laser annealing process mask, the process mask comprises a completely transparent region, a completely light-shielding region and a partial light-transmitting region, wherein the partial light-transmitting regions are distributed in the completely transparent region. In order to change the complete laser energy density distribution, the amorphous material is converted into a polycrystalline material. In a preferred embodiment, the process mask defines a relative shift: the ancient = Cheng Guang ^ includes a plurality of first and second rectangular pattern bits = a first cover, and a mother and a second rectangular pattern are - completely enclosed - the first and second rectangular patterns are arranged parallel to each other perpendicular to the two regions, each The first rectangular pattern corresponds to two rectangles

0773-10407TWF(N1);P92060;amy.ptd Page 7 1127792 V. INSTRUCTIONS (4) A completely opaque area between the patterns, and in each of the first and smear--, at least one non-linear portion of the light The area extends substantially along the direction of the phase a map. The non-linear portion of the above-mentioned light-shielding region may be constituted by a plurality of line segments arranged in a repetitive zigzag manner. In a preferred embodiment, wherein the fully transparent region and the partially transparent region are arranged in a mosaic pattern. In a preferred embodiment, the process reticle defines a relative moving direction, and the process reticle further comprises: a plurality of first and second rectangular patterns on the holographic mask, and each of the first and the second The two rectangular patterns are surrounded by a completely opaque region. The first and second rectangular patterns are respectively arranged in parallel perpendicular to the relative movement direction. Each of the first rectangular patterns corresponds to a completely opaque region between two adjacent second rectangular patterns. And having a mosaic pattern formed by the total light-transmissive region and the partial light-transmitting region in each of the first and second rectangular patterns. The present invention and a method for forming a polycrystalline film layer by laser annealing first, after depositing an amorphous film layer on the substrate, the amorphous film layer, the row/field annealing process The film layer is converted into a polycrystalline film layer, and the grain boundaries of the smectic film layer are non-linearly arranged. In the method of forming a polycrystalline film layer by laser annealing, the amorphous Å and the 口 曰 曰 Japanese film layers may be an amorphous ruthenium film layer and a polycrystalline ruthenium film layer, respectively. In the method of forming a polycrystalline film layer by 曰曰 rate film #二Γ1ΐ, the grain boundaries of the multi-film layer are arranged in a zigzag manner. [Embodiment] In the laser process of converting a non-deuterated system into a polycrystalline system, in order to avoid formation of page 8 0773-10407TWF(m); P92060; amy.ptd 1271792 V. Invention description (5) Continuous straight type The grain boundaries are prominent, so the present invention devises a reticle =: a pattern that controls the junction boundary by changing the penetration energy distribution of the laser by precision. % / The laser annealing process mask of the present invention comprises a completely transparent region and a partially transparent region, wherein a part of the light-transmitting region is uniformly distributed in the process of converting the amorphous material into a polycrystalline material. Nine Covers Μ First Embodiment Referring to Figure 3, there is shown a partial view of a laser annealing process reticle in accordance with a preferred embodiment of the present invention. The oblique line in the figure is a completely opaque field 104, the blank area is a completely transparent area, and the meander line is a partial light transmission area πσ 1 08. During the laser annealing process, the process mask and the substrate are relatively moved to gradually convert the amorphous layer into a polycrystalline layer. The arrow in the figure indicates the relative movement direction of the laser beam. . As shown in the figure, the processing mask 100 corresponds to the laser beam width? Within the range, there are a plurality of rectangular patterns 102a*102b, and are arranged parallel to each other in a direction perpendicular to the relative movement direction X, wherein each of the rectangular patterns 1 〇 2 a and 10 2b is surrounded by a completely opaque area 1 〇 4 The rectangular pattern i〇2a is disposed on the left side, and the rectangular pattern 1 0 2b is disposed on the right side, and each of the rectangular patterns 丨〇2a corresponds to the completely light-shielding region 之间4 between the two adjacent rectangular patterns 丨〇2b. Each of the rectangular heart patterns 102a and 102b is provided with at least one non-linear portion of the light transmitting region 108, and the non-linear portion of the light transmitting region 丨〇8 extends substantially along the relative moving side X. ϋ The above-mentioned non-linear partial light transmission area 丨〇 8, for example, by a plurality of line segments m im 0773 -10407TWF(N1); P92060; amy. ptd 1271792

V. Description of invention (6) Arranged in a tortuous zigzag manner (as shown in Fig. 3, f... and the non-linear part of the light-transmissive area 1〇8; one, and close to the rectangular object 1〇2a# For example, the light transmittance of the light-transmitting region 1〇8 is about 8〇~9〇%, and 4, for each of the rectangular patterns 1023 and 10 Torr, _X 0.020 mra, The spacing between two adjacent two 975 parallel to the relative moving direction x is 0.010 _, and the horizontal spacing between the left rectangular pattern 102a and the slug 102b is 〇. 5 _, each rectangular pattern: two patterns 1 02b The vertical dependence of the peripheral and non-linear portion of the light-transmissive region i 〇8, as shown in Fig. 4. When using this process reticle for the amorphous laser-injection laser annealing process, corresponding to 6-6 of Figure 4 The laser energy distribution state of the tangential amorphous layer is as shown in Fig. 5, the horizontal axis is the relative position, the vertical axis is the energy density of the laser pulse, and the extension line ^ is the critical point of complete melting, but corresponding The laser pulse energy density at the relative position of the partial light transmission region 丨0 8 of the tortuous straight line segment is also lower than that of the adjacent region. Fig. 6 is the use of the above A schematic diagram of the laser annealing of the amorphous film layer by the process mask is referred to as a substrate, for example, a glass substrate, and the reference numeral 160 is an amorphous film layer, and the material is, for example, an amorphous germanium, and the formation method is, for example, Chemical vapor deposition method. Thereafter, the substrate 15 5 is placed on the support 3 0 2 in the reaction chamber, and the laser beam 3 〇〇 is irradiated to the amorphous film layer on the substrate 150 via the process mask 1 And by moving the support (the direction of movement X is the direction indicated by the arrow in the figure), the amorphous film layer 160 is gradually converted into the polycrystalline film layer 11 〇. The polycrystalline film layer 1 1 The distribution of the lattice boundary protrusions 1 1 2 of the crucible, as shown in Fig. 7, is made of the polycrystalline film layer 1 1

0773 -10407TWF(N1);P92060;amy.ptd Page 101271792 Description of invention (7) 莼, the source S of the transistor 1 4 1 , the pole D, the channel area (the arrow in the figure) The relative pattern of the lattice boundary protrusions 1 1 2 is as shown, so that the electrical characteristics of each of the electron hole channels can be made uniform. SECOND EMBODIMENT Referring to Figure 8, there is shown a partial view of an injective annealing process mask of another preferred embodiment of the present invention. Elements in the figures that are identical to the first embodiment are denoted by the same reference numerals. As shown, the fully transparent region 206 and the partially transparent region 2〇8 of the masks 102a and 102b of the process mask are patterned. Laser annealing of a grain-annealed thin film transistor of a laser annealed square crystal to avoid polycrystalline system [Features or Advantages of the Invention The present invention provides a multi-protrusion when a polycrystalline film is formed to form a The present invention provides a distributed partial light transmissive region, a line of protrusions. By using the film-forming layer of the present invention, the grain boundary is the formed thin film transistor, which results in a thin film transistor. Although the present invention has been limited to the present invention, any conventional method does not form a crystalline boundary of the amorphous film layer. The electrical properties of the lines are more consistent. The reticle of the process comprises a uniform aa grain boundary forming a continuous straight reticle for linear arrangement of the ray, and a preferred embodiment of the grain in the channel region is disclosed by the skilled person, and the polycrystalline system formed by the shot annealing is thus utilized. The distribution of the boundary of the film layer is relatively uniform and the electrical properties are relatively uniform. The road is as above, but it is not used without departing from the spirit of the present invention.

0773 -10407TWF(N1);P92060;amy.ptd 筮百 1271792

0773 -10407TWF(N1);P92060;amy.ptd Page 121271792 BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a view showing a thin film transistor formed by using a polycrystalline germanium film formed by a conventional continuous lateral solidification method to prepare a thin film transistor. Schematic diagram of the channel direction. Figure 2 shows the normal and abnormal drain current-gate voltage curves. Figure 3 is a partial view showing a laser annealing process reticle in accordance with a preferred embodiment of the present invention. Fig. 4 is a specific example of the pattern size relationship of the laser annealing process mask of Fig. 3. Figure 5 is the laser energy distribution state of the amorphous layer corresponding to the 6-6 tangential line of Fig. 4, the horizontal axis is the relative position, the vertical axis is the energy density of the laser pulse, and the extension line E is the complete melting. The critical point. Figure 6 is a schematic diagram of a laser annealing process. Figure 7 is a diagram showing the distribution of lattice boundary protrusions of the amorphous film layer after laser annealing of the amorphous film layer by using the process mask of the first preferred embodiment of the present invention, and utilizing The relative pattern relationship between the source-drain-channel region of the transistor made of the polycrystalline film layer and the lattice boundary protrusion. Figure 8 is a partial view showing a laser annealing process mask of another preferred embodiment of the present invention. [Simplified symbol] Width of the melted 矽 section (laser beam width): W ; Thin film transistor: 4 1 , 1 4 1 ; Relative movement direction · X,

0773- 10407TWF(N1);P92060;amy.ptd Page 131271792 Schematic description of process mask: 1 0 0 ; Rectangular pattern: 1 02a, 1 02b; Complete shading area: 1 04 ; Complete light transmission area: 106 2 0 6 ; Partially transparent area: 108, 208; Critical point of complete melting: E; Polycrystalline film layer: 11 0; Lattice boundary protrusion: 11 2 ; Laser beam: 300; Substrate :1 5 0 ; Amorphous ruthenium film layer · 1 60, support base: 30 2.

0773 -10407TWF(N1);P92060;amy.ptd第14页

Claims (1)

Bu 7 §f (US) is replacing an I 1C year [. Month (I 曰Revision of the six, the scope of the patent application 1 · · a laser annealing, a complete full shading, 2 · hood, its light zone package shading area is used to change the application of the complex rectangular pattern system Along each first rectangular full shading area, each of the first and the first spears is arranged side by side, and the patented mask is first perpendicular to the pattern system 3. The cover is curved. The cover, the arrangement thereof. 5. The cover, the optical zone package, such as the non-arrangement in the application, is composed of the patented straight line of the light-transparent two-rectangle patent. The patent is fully transparent as in the patent application. a plurality of first rectangular patterns are perpendicular to each of the first rectangular pattern lines; and the process masks are arranged side by side in the full light-shielding area, and include: a completely transparent region, a partial light-transmitting region, wherein the completely transparent region is The portion of the light-transmitting region is distributed in the laser energy density distribution of the fully transparent region of the completely transparent region. The process light of the laser annealing described in the first item defines a relative moving direction, and the complete transparent Second moment a pattern, and the first and second relative movement directions are respectively arranged in parallel, and the complete area between the two adjacent second rectangular patterns is a non-linear partial light transmission area, and the pattern is located The process light of the laser annealing described in item 2 is a process light that is laser-annealed by a plurality of line segments. The portion of the glazing zone is one. The mosaic pattern ^ ^1 shell described in the laser annealing process light 疋 ^ has a relative movement direction, and the completely diaphoresing mouth - the moment 图 图 m : : : : : : : : : : : : : : : : : : : : : : : , , , , , A moving direction is arranged in parallel, and the end of the two adjacent 兮笙-豕弟二 rectangle patterns 0773-10407TWFl(Nl).ptc Page 15 1271792 _ Case No. 93106019_ Year Month _ Amendment _ VI. Patent Application Scope A mosaic pattern formed by the completely transparent region and the partially transparent region is located at Among each of the first and second rectangular patterns. 6. The laser anneal process reticle of claim 1, wherein a portion of the light transmissive region has a light transmittance of 80 to 90%. 7. A method of forming a polycrystalline film layer by laser annealing, comprising: providing an amorphous film layer on a substrate; and performing a continuous lateral solidification laser annealing process on the amorphous film layer, Converting the amorphous film layer into a polycrystalline film layer, and the grain boundary of the polycrystalline film layer is non-linearly arranged, wherein the laser annealing process comprises using a process mask, the process mask includes a completely transparent region, a completely light-shielding region and a portion of the light-transmitting region, wherein the completely transparent region is surrounded by the completely light-shielding region, and the partial light-transmitting region is distributed in the completely transparent region , to change the laser energy density distribution of the completely transparent region. 8. The method for forming a polycrystalline film layer by laser annealing according to claim 7, wherein the amorphous film layer and the polycrystalline film layer are an amorphous stone layer and a Polycrystalline stone layer. 9. The method of forming a polycrystalline film layer by laser annealing as described in claim 7, wherein the grain boundaries of the polycrystalline film layer are arranged in a meandering manner. The method for forming a polycrystalline film layer by laser annealing according to claim 7, wherein the process mask defines a relative moving direction, and the complete light transmitting region includes a plurality of first and second portions. a rectangular pattern, wherein the first and second rectangular patterns are respectively arranged in parallel perpendicular to the relative moving direction, and each of the first rectangular patterns is adjacent to the second rectangle 0773-10407TWFl(Nl).ptc Page 16 1271792 _ Case No. 93106019_年月日日_«_ 6. The completely opaque area between the patented range patterns is side by side; wherein the partially transparent area is a non-linear part A light transmissive region is located in each of the first and second rectangular patterns. 11. A method of forming a polycrystalline film layer by laser annealing as described in claim 10, wherein the non-linear portion of the light-shielding region is formed by repeating a plurality of line segments in a repeating meandering manner. 1 2. The method of forming a polycrystalline film layer by laser annealing according to claim 7, wherein the completely transparent region and the partially transparent region are arranged in a mosaic pattern. 1 . The method of forming a polycrystalline film layer by laser annealing according to claim 7 , wherein the process mask defines a relative moving direction, and the complete light transmitting region comprises a plurality of first and second portions. a rectangular pattern, wherein the first and second rectangular patterns are respectively disposed in parallel along a direction perpendicular to the relative movement direction, and the first light shielding area between each of the first rectangular patterns and the two adjacent second rectangular patterns Side by side; and a mosaic pattern formed by the fully transparent region and the partially transparent region is located in each of the first and second rectangular patterns. The method of forming a polycrystalline film layer by laser annealing as described in claim 7, wherein the light transmissive portion of the process mask has a light transmittance of 80 to 90%. 0773-10407TWFl(Nl).ptc Page 17