TWI574336B - Reclaimed susceptor and method for repairing the same - Google Patents

Description

Recycled wafer carrier tray and repairing method thereof

The invention relates to a recycled wafer carrier disk and a repairing method thereof, in particular to a wafer carrier disk for a metal organic chemical vapor deposition (MOCVD) epitaxial furnace [susceptor, wafer carrier or substrate] Recycling and repair of the holder].

High-power high-brightness gallium nitride [GaN] light emitting diodes (LEDs) are the core materials for solid-state lighting, and MOCVD epitaxial furnaces are indispensable for making GaN-based LEDs.

MOCVD epitaxial furnace integrates precision machinery, semiconductor materials, vacuum electronics, fluid mechanics, thermals, optics, chemistry and other disciplines. It is a specialized equipment for the manufacture of advanced semiconductor materials with high degree of automation, high price and high technology integration.

The MOCVD epitaxial process is a method of vapor phase epitaxial growth of a semiconductor material by thermal decomposition of an organometallic compound.

The main system components of the MOCVD epitaxial furnace include: reaction chamber, reactive gas supply system and exhaust gas treatment system; the reaction chamber is where the gas mixes and reacts, and the chamber is connected to the reaction gas supply system by nozzle or jet head [showerhead] The reaction gases are mixed and delivered to the surface of the epitaxial wafer.

The cavity includes a wafer carrier, a heater, etc., and the wafer carrier needs to be effectively sucked. The energy provided by the heater is received and heated by direct thermal contact with the wafer or by thermal radiation to achieve the temperature required for the epitaxial growth reaction.

Therefore, the wafer carrier must have good electromagnetic wave absorption and heat transfer properties to ensure uniform temperature distribution on the disk surface; usually a well-designed MOCVD reaction cavity, in order to accurately control the wavelength uniformity of LED epitaxial wafers, the wafer carrier disk The heater is required to provide optimum wafer temperature uniformity to deposit a good quality epitaxial layer, so the wafer carrier is one of the important components in the MOCVD epitaxial furnace.

Figure 1 is a schematic diagram of a conventional monolithic wafer carrier, and Figure 2 is a schematic diagram of a conventional multi-chip wafer carrier. Referring to Figure 3, a conventional wafer carrier (10) is generally used. The graphite substrate (20) was fabricated, and a ruthenium carbide [SiC] plating layer (30) having a thickness of about 70 to 120 μm was deposited on the surface by CVD.

Among them, the main functions of the ruthenium carbide coating (30) are as follows:

First point: Protect the graphite substrate (20) from the ammonia [NH ₃ ] reaction gas in the MOCVD epitaxial process; the tantalum carbide material has excellent high temperature chemical stability, and the CVD tantalum carbide coating (30) It is a dense vapor-grown polycrystalline film that can effectively isolate MOCVD process gases after the surface of the graphite is coated with tantalum.

The second point: the graphite substrate (20) is easy to vent out at high temperature [outgassing], the released gas will pollute the reaction atmosphere of the MOCVD process, reduce the quality of the epitaxial layer, and the conventional wafer carrier disk (10) coated with graphite After the upper carbonized ruthenium plating layer (30) is sealed, the deflation phenomenon can be effectively prevented.

The third point: to improve the heat transfer properties of the conventional wafer carrier disk (10) made of graphite. Since the heat conduction and thermal emissivity of the tantalum carbide are higher than that of graphite, a better layer of the disk can be obtained by plating a layer of tantalum carbide on the surface of the graphite. Gentle.

Fourth point: Since the surface of the graphite material is easily peeled off to generate dust, it will cause particle contamination of the epitaxial wafer, and it is difficult to form a high hardness and wear-resistant surface layer after coating with CVD carbonized ruthenium. Produce particles.

During the use of the wafer carrier disk, it may be caused by a collision of relative movement of the wafer, a collision of a mechanical transfer process, or an external collision such as an accidental collision, resulting in a chipping or a ruthenium carbide layer (30). The damaged condition causes the graphite substrate (20) to be exposed, and the conventional wafer carrier tray (10) must be scrapped.

Even if there is no such situation, usually the conventional wafer carrier disk (10) may be cracked due to thermal stress or slight collision or scratch on the surface after a period of use, or it may be caused by ammonia [NH ₃ The etching acts on the defect of the tantalum carbide coating (30) to create an etch pit.

These cracks or etched holes are accelerated or expanded with the help of cyclic thermal stress during the operation of the carrier. Once the graphite substrate (20) is passed through the ruthenium carbide coating (30), an etched graphite bottom is formed. The reaction gas channel of the material (20).

Ammonia gas [NH ₃ ] begins to explain atomic hydrogen [H] at temperatures above 400 ° C. The carrier disk temperature of GaN-based LEDs during MOCVD epitaxial process can be as high as about 1200 ° C. At this high temperature, ammonia gas will rapidly A large amount of atomic hydrogen is explained. The atomic hydrogen is highly reactive to the carbon of the graphite phase. If the graphite substrate (20) is contacted by enlarged cracks or etched holes, the atomic hydrogen will strongly etch the graphite. The reaction generates gaseous hydrocarbons and is mixed into the atmosphere of epitaxial epitaxial growth, so that the concentration of carbon in the epitaxial layer gradually increases, which ultimately affects the wavelength and brightness of the LEDs grown. At this time, the carrier disk needs to be replaced. Update.

When the graphite substrate (20) is etched by a large amount of atomic hydrogen, the surface of the ruthenium carbide substrate whose substrate is emptied is left. Usually, the color of the ruthenium carbide coating (30) changes from the original blue-gray to a yellowish color. .

The suspended ruthenium carbide coating (30) is easily broken, peeled, or collapsed into a hole during subsequent use. As shown in Fig. 4, a large-area graphite substrate (20) is exposed. The carrier tray must be scrapped; in fact, most of the silicon carbide coatings (100) are scrapped on the wafer carrier tray (100) except for the visible holes visible in the naked eye and some tiny cracks and etch holes in the ruthenium carbide coating (30). 30) Still intact, the overall wafer carrier structure is still intact.

However, wafer carriers that have been scrapped for a long time can only be discarded and eventually become commercial waste. Recycled wafer carrier trays are still not available.

In view of the above, how to provide an effective recycled wafer carrier disk and a repair method thereof are the subject of improvement of the present invention.

The object of the present invention is to provide a recycled wafer carrier disk capable of solving the problem of scrapping a wafer carrier disk and a repairing method thereof.

In order to solve the above problems and achieve the object of the present invention, the technical means of the present invention is realized by the structure of the recycled wafer carrier, especially a recycled wafer carrier, the recycled wafer carrier. (200) is produced by reprocessing a scrap wafer carrier (100), which is a graphite substrate (20) and is coated with an original tantalum carbide coating (102) on the surface. The scrapped wafer carrier tray (100) has a damaged hole (101) which is a recess formed on the graphite substrate (20) and the original tantalum carbide coating (102), characterized in that it is scrapped. The damaged hole (101) of the wafer carrier disk (100) is filled with the carbonized cerium-based ceramic composite material (C) to form a complete repairing area (1); the whole of the scrapped wafer carrier disk (100) The surface and the surface of the repaired area (1) are more evenly coated with a newly deposited layer of tantalum carbide (2).

More preferably, the original ruthenium carbide coating (102) further comprises a crack (103) or an etched hole (104), and uniformly bonds the newly deposited tantalum carbide layer in the crack (103) or the etched hole (104). (2).

More preferably, the cerium carbide-based ceramic composite (C) comprises a ceramic powder (S) and a cerium carbide matrix material (M).

More preferably, the ceramic powder (S) is one of the following or a mixture thereof: graphite powder, diamond powder, cerium powder, cerium carbide [SiC] powder, boron carbide [B ₄ C] powder, boron nitride [BN Powder, aluminum nitride [AlN] powder, tantalum nitride [Si ₃ N ₄ ] powder, alumina [Al ₂ O ₃ ] powder, yttria [SiO ₂ ] powder.

More preferably, the ceramic powder (S) preferably has a particle diameter of between 0.1 μm and 40 μm.

More preferably, the newly deposited tantalum carbide layer (2) has a thickness of less than 25 μm, more preferably less than 10 μm.

In order to solve the above problems and achieve the object of the present invention, the technical means for repairing the present invention is achieved by a method for repairing a recycled wafer carrier disk, which is processed for a scrap wafer carrier (100). The scrap wafer carrier (100) is a graphite substrate (20) and is coated with an original tantalum carbide coating (102) on the surface, and the scrap wafer carrier (100) has a damaged hole (101). The hole (101) is a recess formed on the graphite substrate (20) and the original ruthenium carbide coating (102); the repair method is as follows: firstly, the ceramic powder (S) is mixed with a binder (Y), and stirred into a a clay-like ceramic powder preform material (P), and then filling the ceramic powder preform material (P) into the damaged hole (101) of the scrap wafer carrier disk (100) to form a repairing zone (1); Then, the scrap wafer carrier (100) is subjected to chemical vapor infiltration [CVI] tantalum carbide, and the ceramic powder preform material (P) is bonded to the repair by a vapor deposited tantalum carbide matrix material (M). Zone (1), becoming a carbonized bismuth-based ceramic composite (C) and simultaneously on the scrap wafer carrier (100) Such repair and surface area (1) silicon carbide layer (2) surface, a new layer deposited uniformly coated, eventually recycled wafer susceptor (200).

More preferably, in the repairing method, the original tantalum carbide coating (102) further includes cracks (103) or etching holes (104), and the chemical vapor infiltration [CVI] tantalum carbide allows the reaction gas to permeate. Entering the crack (103) or the etch hole (104) for vapor deposition of the ruthenium carbide reaction.

More preferably, in the repairing method, the ceramic powder (S) is one of the following or a mixture thereof: graphite powder, diamond powder, cerium powder, cerium carbide [SiC] powder, boron carbide [B ₄ C] powder, nitrogen Boron [BN] powder, aluminum nitride [AlN] powder, tantalum nitride [Si ₃ N ₄ ] powder, alumina [Al ₂ O ₃ ] powder, yttria [SiO ₂ ] powder; and select tantalum carbide [ SiC] powder is preferred.

Compared with the prior art, the present invention has the following effects:

In the present invention, the exposed graphite substrate can be completely coated again by filling the carbonized bismuth-based ceramic composite material at the damaged hole of the scrap wafer carrier and coating a newly deposited tantalum carbide layer; in addition, the newly deposited carbonization The bismuth material can also heal the cracks and etch holes in the original ruthenium carbide coating of the scrap wafer carrier; therefore, the scrapped carrier can restore its original characteristics and be recycled again, which can greatly save the LED epitaxial process. Consumables and reduce unnecessary business waste.

1‧‧‧Repair area

2‧‧‧New deposits of tantalum carbide

10‧‧‧Traditional wafer carrier

20‧‧‧Graphite substrate

30‧‧‧Carbide coating

100‧‧‧ scrapped wafer carrier tray

101‧‧‧damaged holes

102‧‧‧Original bismuth carbide coating

103‧‧‧ crack

104‧‧‧Erosion

200‧‧‧Recycled wafer carrier tray

H‧‧‧ pocket depth

N‧‧‧ surface roughness

F‧‧‧pan flatness

S‧‧‧Ceramic powder

Y‧‧‧Adhesive

P‧‧‧Ceramic powder preform material

M‧‧‧Carbide matrix material

C‧‧‧Carbide-based ceramic composites

Figure 1: Schematic diagram of a conventional monolithic wafer carrier.

Figure 2: Schematic diagram of a conventional multi-chip wafer carrier.

Figure 3 is a cross-sectional view of the A-A of the wafer carrier of Figure 2;

Figure 4: Schematic diagram of the broken hole of the scrap wafer carrier.

Figure 5: Schematic diagram of the broken hole of the scrap wafer carrier to fill the ceramic powder preform material to form the repaired area.

Fig. 6 is a schematic cross-sectional view showing the carrier wafer of the recycled wafer after the chemical vapor infiltration of the tantalum carbide is processed in Fig. 5.

The following is a detailed description of the following embodiments according to the drawings:

As shown in Fig. 5, the repairing method of the present invention firstly mixes the ceramic powder (S) with the binder (Y) and stirs it into a clay-like ceramic powder preform [preform] material. (P), the ceramic powder preform material (P) is filled in the damaged hole (101) of the scrap wafer carrying tray (100) to form a repaired area (1).

Next, please refer to Fig. 6, and then carry out chemical vapor infiltration (CVI) niobium carbide on the scrap wafer carrier (100) to make the ceramic powder preform material (P) to be vapor deposited. a carbon nanotube substrate [Mtrix] material (M), bonded to the repaired area (1), and uniformly coated with a new deposited tantalum carbide layer (2) on the entire surface of the scrap wafer carrier disk (100) and The surface of the repaired area (1) finally becomes a recycled wafer carrier tray (200).

The adhesive (Y) used in the repairing method of the present invention is preferably an organic binder, such as one of the following: polyvinyl alcohol, starch, polyvinyl acetate, polystyrene, etc., wherein the binder (Y) In the chemical vapor infiltration process, it will be vaporized due to high temperature thermal decomposition.

When the niobium carbide is deposited by the chemical vapor infiltration [CVI] method, the chemical vapor deposition [CVD] reaction is preferably carried out using a reaction gas of methyltrichlorosilane (CH3SiCl3, methyltrichlorosilane) and hydrogen [H2].

It is important not to increase the thickness of the original surface of the original ruthenium carbide coating (102) so as not to change the pocket [pocket] depth (H), disk surface roughness (N), and disk surface flatness (F) [Please refer to Fig. 3], which in turn affects the temperature uniformity of the wafers carried thereon, the newly deposited tantalum carbide layer (2) has a thickness of less than 25 μm, more preferably less than 10 μm, as shown in Fig. 6.

The chemical vapor infiltration [CVI] method is used to minimize the deposition of tantalum carbide on the surface of the carrier disk, and the tantalum carbide is deposited on the surface of the ceramic powder (S) of the ceramic powder preform material (P), and the ceramic powder (S). The gap between the gap and the inner surface of the damaged hole (101) causes the ceramic powder preform material (P) to be bonded to the repaired area (1) by vapor deposition of the tantalum carbide base material (M). The tantalum-based ceramic composite (C) is carbon-coated and the damaged graphite substrate (20) is completely coated with a newly deposited tantalum carbide layer (2).

Still able to increase the thickness of the original ruthenium carbide coating (102) At the damaged hole (101) of the carrier disk, a thick protective layer of cerium-based ceramic composite material is formed to protect the graphite substrate (20).

Furthermore, the chemical vapor infiltration [CVI] method can also allow the reaction gas to penetrate into the crack (103) or the etched hole (104) of the original ruthenium carbide coating (102), and carry out the reaction of vapor deposition of ruthenium carbide. The internal space of the crack (103) and the etched hole (104) is re-filled with the cerium carbide material to heal the damaged original strontium carbide coating (102).

In the method of the present invention, the ceramic powder (S) used is one of the following or a mixture thereof: graphite powder, diamond powder, cerium powder, cerium carbide [SiC] powder, boron carbide [B ₄ C] powder, nitrogen. Boron [BN] powder, aluminum nitride [AlN] powder, tantalum nitride [Si ₃ N ₄ ] powder, alumina [Al ₂ O ₃ ] powder, yttria [SiO ₂ ] powder.

In the above ceramic powder (S), a cerium carbide (SiC) powder is preferably selected; and the ceramic powder (S) preferably has a particle diameter of 0.1 μm to 40 μm.

The embodiments of the present invention are described in detail with reference to the embodiments shown in the drawings. The conforming modification changes should fall within the scope of the invention as long as they are within the scope of the equal effect.

1‧‧‧Repair area

2‧‧‧Newly deposited tantalum carbide layer

20‧‧‧Graphite substrate

101‧‧‧damaged holes

102‧‧‧Original bismuth carbide coating

200‧‧‧Recycled wafer carrier tray

S‧‧‧Ceramic powder

M‧‧‧Carbide matrix material

C‧‧‧Carbide-based ceramic composites

Claims (7)

A recycled wafer carrier tray, the recycled wafer carrier tray (200) being reworked for a scrap wafer carrier tray (100), the scrap wafer carrier tray (100) being a graphite substrate (20) and The surface is plated with an original ruthenium carbide coating (102) having a damaged hole (101) on the scrap wafer carrier (100). The hole (101) is on the graphite substrate (20) and the original ruthenium carbide coating. The recess formed on (102) is characterized in that, at the damaged hole (101) of the scrap wafer carrying tray (100), the carbonized cerium-based ceramic composite material (C) is filled to form a complete repairing area ( 1); on the entire surface of the scrapped wafer carrier disk (100) and the surface of the repairing area (1), more uniformly coated with a newly deposited layer of tantalum carbide (2); the carbonized base ceramic composite material (C) ), which comprises a ceramic powder (S) and a tantalum carbide base material (M). The recycled wafer carrier tray of claim 1, wherein: the original ruthenium carbide coating (102) further comprises a crack (103) or an etch hole (104), and the crack (103) or the etch hole ( 104) uniformly bonding the newly deposited tantalum carbide layer (2). The recycled wafer carrier tray according to claim 1, wherein the ceramic powder (S) is one of the following or a mixture thereof: graphite powder, diamond powder, tantalum powder, tantalum carbide [SiC] powder, boron carbide [ B ₄ C] powder, boron nitride [BN] powder, aluminum nitride [AlN] powder, tantalum nitride [Si ₃ N ₄ ] powder, alumina [Al ₂ O ₃ ] powder, yttrium oxide [SiO ₂ ] powder . The recycled wafer carrier tray according to claim 3, wherein the ceramic powder (S) has a preferred particle diameter of between 0.1 μm and 40 μm. The recycled wafer carrier tray according to claim 1, wherein the newly deposited tantalum carbide layer (2) has a thickness of less than 25 μm, more preferably less than 10 μm. A method for repairing a recycled wafer carrier disk, which is fabricated by reprocessing a scrap wafer carrier (100), which is a graphite substrate (20) and has an original plated surface a ruthenium carbide coating (102), and the scrap wafer carrier (100) has a damaged hole (101) formed on the graphite substrate (20) and the original ruthenium carbide coating (102). Depression; the repair method is as follows: firstly, the ceramic powder (S) is mixed with a binder (Y), and stirred into a clay-like ceramic powder preform material (P), and then the ceramic powder preform material (P) Filling the repaired area (1) at the damaged hole (101) of the scrapped wafer carrier (100); and then subjecting the scrapped wafer carrier (100) to chemical vapor infiltration [CVI] tantalum carbide to make the ceramic The powder preform material (P) is bonded to the repairing zone (1) by a vapor deposited tantalum carbide matrix material (M) to form a tantalum-based ceramic composite material (C) and simultaneously on the scrap wafer carrier tray. (100) The entire surface and the surface of the repaired area (1) are uniformly coated with a newly deposited layer of tantalum carbide (2) to form a recycled crystal. The carrier plate (200); said ceramic powder (S) for SiC [the SiC] powder. The method for repairing a recycled wafer carrier tray according to claim 6, wherein: the original tantalum carbide coating (102) further comprises a crack (103) or an etching hole (104), and the chemical vapor infiltration [ CVI] bismuth carbide, which allows the reaction gas to penetrate into the crack (103) or the etch hole (104) for vapor deposition of the ruthenium carbide reaction.