阅读说明：本技术 一种提升GaAs晶片强度的处理方法 (Processing method for improving strength of GaAs wafer ) 是由 许子俊 马曾增 陈伟 于 2021-08-12 设计创作，主要内容包括：本发明及一种提升GaAs晶片强度的处理方法,包括按照将GaAs晶片晶向特征将其与工装粘接,在采用斜喷淋切割方式对工装晶片与工装粘接位置进行切割后,对GaAs晶片表面研磨,再将其置于腐蚀锅中,使用热碱液对该GaAs晶片腐蚀,经过清洗设备和抛光设备处理最后干燥。该提升GaAs晶片强度的处理方法,通过改变翘曲Bow值的变化,以改变衬底在外延过程中产生的边缘缺陷和外延式裂片问题,减少衬底在外延生长过程中产生的破损率,提高外延生长过程中的成品率。(The invention relates to a processing method for improving the strength of a GaAs wafer, which comprises the steps of bonding the GaAs wafer with a tool according to the crystal orientation characteristic of the GaAs wafer, cutting the bonding position of the tool wafer and the tool in an inclined spraying cutting mode, grinding the surface of the GaAs wafer, placing the GaAs wafer in a corrosion pot, corroding the GaAs wafer by using hot alkali liquor, processing by cleaning equipment and polishing equipment, and finally drying. According to the processing method for improving the strength of the GaAs wafer, the edge defects and epitaxial cracking problems generated in the epitaxial growth process of the substrate are changed by changing the change of the warping Bow value, the damage rate of the substrate generated in the epitaxial growth process is reduced, and the yield in the epitaxial growth process is improved.)

1. A processing method for improving the strength of a GaAs wafer is characterized by comprising the following steps:

step 1: selecting a bonding position according to the crystal orientation characteristics of the GaAs wafer, coating photoresist on the surface of the GaAs wafer, spraying an adhesive A on the photoresist, spraying an adhesive B on the surface of the tool, bonding the tool and the GaAs wafer by using the adhesive A and the adhesive B, and entering the step 2;

step 2: mounting the tool bonded with the GaAs wafer obtained in the step 2 on a thinning clamp of a cutting device, adjusting the cutting azimuth structure of the cutting device, cutting the bonding position of the tool wafer and the tool by adopting an inclined spraying cutting mode to change the requirement that the Bow value is a plus value, and entering a step 3;

and step 3: taking the tool bonded with the GaAs wafer down from the thinning clamp of the cutting device, then installing the tool bonded with the GaAs wafer on the thinning clamp of the crystal orientation angle grinding equipment, grinding the GaAs wafer by using a grinding disc and grinding slurry which are pasted with grinding cloth, and entering the step 4;

and 4, step 4: taking down the GaAs wafer tool arranged on the thinning clamp of the crystal orientation angle grinding equipment in the step 3, placing the tool in an etching pot, pouring hot alkali liquor into the etching pot to carry out heating etching on the GaAs wafer bonded on the surface of the tool, wherein the etching amount is about 10um, obtaining the GaAs wafer with the cutting wafer warping degree of 1-5 um, and entering the step 5;

and 5: and (4) taking out the tool which is obtained in the step (4) and bonded with the GaAs wafer after low corrosion treatment, cleaning the tool by ultrasonic cleaning equipment, putting the tool into a clamp again to precisely polish the GaAs wafer, and finally taking out the tool and drying the GaAs wafer by centrifugal drying equipment.

2. The processing method for improving the strength of the GaAs wafer as claimed in claim 1, wherein: in the step 4, the hot alkali liquor comprises the following components in percentage by volume: 73 to 77 percent of hydrogen peroxide, 2.8 to 5 percent of concentrated sulfuric acid, 6.7 to 10 percent of glacial acetic acid and 8.5 to 11.5 percent of concentrated hydrochloric acid.

3. The processing method for improving the strength of the GaAs wafer as claimed in claim 1, wherein: in the step 3, the grinding cloth is monocrystalline diamond grinding cloth with a nano artificial diamond coating on the surface, the particle size of diamond particles in the coating is 400-600 nm, and the rotation speed of a grinding disc is 120-180 r/min.

4. The processing method for improving the strength of the GaAs wafer as claimed in claim 1, wherein: in step 3, the grinding slurry comprises the following components: a lubricant, a surfactant, a dispersant, deionized water and a pH value regulator; the weight percentage is as follows: 0.5 to 4 percent of lubricant; 0.5 to 10 percent of active agent; 1 to 4 percent of dispersant; 80% -94% of deionized water; pH regulators: 0.1 to 1 percent; the pH value of the grinding slurry is 6.5-11.5, and the flow rate of the slurry is 2-3 ml/s.

5. The processing method for improving the strength of the GaAs wafer as claimed in claim 1, wherein: in step 1, the adhesive A sprayed on the photoresist is hexamethyldisilane adhesive.

6. The processing method for improving the strength of the GaAs wafer as claimed in claim 1, wherein: in the step 1, the adhesive B is sprayed on the photoresist by spraying ethylene glycol titanate adhesive on the surface of the tool in a vacuum environment with the temperature of 135-150 ℃ and the vacuum degree of less than or equal to 1 x 10 < -2 > mbar.

7. The processing method for improving the strength of the GaAs wafer as claimed in claim 1, wherein: in the step 1, after the tool is bonded with the GaAs wafer, the tool bonded with the GaAs wafer is cooled to room temperature of 20-24 ℃.

[ technical field ] A method for producing a semiconductor device

The invention relates to the field of LED wafer production processes, in particular to a processing method for improving the strength of a GaAs wafer.

[ background of the invention ]

During the production of the wafer, the processing technology of the wafer may affect the strength of the wafer, and the possible affecting technologies are: slicing, grinding, corroding and polishing, wherein the slicing and grinding inevitably have certain damage, and the polishing and the corroding can remove part or all of the damage, but because the requirements of the acidic corrosive liquid on vessels and corrosion conditions are higher, the brightness of the surface of the wafer after corrosion is inconsistent, and the wafer is flaked, so that the wafer is fragile after epitaxy, and the yield is reduced. In view of the above-mentioned problems, it is desirable to design a processing method for improving the strength of GaAs wafers to improve the breakage rate caused by the hard force after the wafer epitaxy.

[ summary of the invention ]

In order to solve the above problems, the present invention aims to provide a processing method for improving the strength of a GaAs wafer, which solves the problems of the existing method that the brightness of the surface of the wafer after etching is inconsistent and the wafer is fragile after the wafer is subjected to epitaxy due to high requirements of the acidic etching solution on vessels and etching conditions, and the yield is reduced.

In order to achieve the purpose, the invention adopts the technical scheme that: a processing method for improving the strength of a GaAs wafer is carried out according to the following steps:

step 1: selecting a bonding position according to the crystal orientation characteristics of the GaAs wafer, coating photoresist on the surface of the GaAs wafer, spraying an adhesive A on the photoresist, spraying an adhesive B on the surface of the tool, bonding the tool and the GaAs wafer by using the adhesive A and the adhesive B, and entering the step 2;

step 2: mounting the tool bonded with the GaAs wafer obtained in the step 2 on a thinning clamp of a cutting device, adjusting the cutting azimuth structure of the cutting device, cutting the bonding position of the tool wafer and the tool by adopting an inclined spraying cutting mode to change the requirement that the Bow value is a plus value, and entering a step 3;

and step 3: taking the tool bonded with the GaAs wafer down from the thinning clamp of the cutting device, then installing the tool bonded with the GaAs wafer on the thinning clamp of the crystal orientation angle grinding equipment, grinding the GaAs wafer by using a grinding disc and grinding slurry which are pasted with grinding cloth, and entering the step 4;

and 4, step 4: taking down the GaAs wafer tool arranged on the thinning clamp of the crystal orientation angle grinding equipment in the step 3, placing the tool in an etching pot, pouring hot alkali liquor into the etching pot to carry out heating etching on the GaAs wafer bonded on the surface of the tool, wherein the etching amount is about 10um, obtaining the GaAs wafer with the cutting wafer warping degree of 1-5 um, and entering the step 5;

and 5: and (4) taking out the tool which is obtained in the step (4) and bonded with the GaAs wafer after low corrosion treatment, cleaning the tool by ultrasonic cleaning equipment, putting the tool into a clamp again to precisely polish the GaAs wafer, and finally taking out the tool and drying the GaAs wafer by centrifugal drying equipment.

The processing method for improving the strength of the GaAs wafer is further provided with the following steps: in the step 4, the hot alkali liquor comprises the following components in percentage by volume: 73 to 77 percent of hydrogen peroxide, 2.8 to 5 percent of concentrated sulfuric acid, 6.7 to 10 percent of glacial acetic acid and 8.5 to 11.5 percent of concentrated hydrochloric acid.

The processing method for improving the strength of the GaAs wafer is further provided with the following steps: in the step 3, the grinding cloth is monocrystalline diamond grinding cloth with a nano artificial diamond coating on the surface, the particle size of diamond particles in the coating is 400-600 nm, and the rotation speed of a grinding disc is 120-180 r/min.

The processing method for improving the strength of the GaAs wafer is further provided with the following steps: in the step 3, the grinding slurry comprises the following components: a lubricant, a surfactant, a dispersant, deionized water and a pH value regulator; the weight percentage is as follows: 0.5 to 4 percent of lubricant; 0.5 to 10 percent of active agent; 1 to 4 percent of dispersant; 80% -94% of deionized water; pH regulators: 0.1 to 1 percent; the pH value of the grinding slurry is 6.5-11.5, and the flow rate of the slurry is 2-3 ml/s.

The processing method for improving the strength of the GaAs wafer is further provided with the following steps: in the step 1, the adhesive A sprayed on the photoresist is hexamethyldisilane adhesive.

The processing method for improving the strength of the GaAs wafer is further provided with the following steps: in the step 1, the adhesive B is sprayed on the photoresist by spraying ethylene glycol titanate adhesive on the surface of the tool in a vacuum environment with the temperature of 135-150 ℃ and the vacuum degree of less than or equal to 1 x 10 < -2 > mbar.

The processing method for improving the strength of the GaAs wafer is further provided with the following steps: in the step 1, after the tool is bonded with the GaAs wafer, the process further comprises cooling the tool bonded with the GaAs wafer to room temperature of 20-24 ℃.

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

according to the processing method for improving the strength of the GaAs wafer, the problem of edge defects and epitaxial cracking of the substrate in the epitaxial growth process is solved by changing the change of the warping Bow value, the damage rate of the substrate in the epitaxial growth process can be reduced, and the yield in the epitaxial growth process is improved.

[ detailed description ] embodiments

The processing method for improving the strength of the GaAs wafer according to the present invention is further described in detail with reference to the following embodiments.

Example 1

The processing method for improving the strength of the GaAs wafer comprises the following steps:

step 1: selecting a bonding position according to the crystal orientation characteristics of a GaAs wafer, coating photoresist on the surface of the GaAs wafer, spraying an adhesive A on the photoresist, wherein the adhesive A is a hexamethyldisilane adhesive, placing a tool in a vacuum environment with the temperature of 135-150 ℃ and the vacuum degree of less than or equal to 1 x 10 < -2 > mbar, spraying an adhesive B on the surface of the tool, wherein the adhesive B is a glycol titanate adhesive, bonding the tool and the GaAs wafer by using the adhesive A and the adhesive B, cooling the tool bonded with the GaAs wafer to the room temperature of 20-24 ℃, and entering a step 2;

step 2: mounting the tool bonded with the GaAs wafer obtained in the step 2 on a thinning clamp of a cutting device, adjusting the cutting azimuth structure of the cutting device, cutting the bonding position of the tool wafer and the tool by adopting an inclined spraying cutting mode to change the requirement that the Bow value is a plus value, and entering a step 3;

and step 3: the tool bonded with the GaAs wafer is taken down from the thinning clamp of the cutting device, the tool bonded with the GaAs wafer is installed on the thinning clamp of the crystal orientation angle grinding equipment, the grinding disc bonded with the grinding cloth and the grinding slurry are adopted to grind the GaAs wafer, the grinding cloth adopts single crystal diamond grinding cloth with a nano artificial diamond coating on the surface, the grain diameter of diamond grains in the coating is 400 nm-600 nm, the rotating speed of the grinding disc is 120-180 r/min, and the grinding slurry comprises the following components: a lubricant, a surfactant, a dispersant, deionized water and a pH value regulator; the weight percentage is as follows: 0.5 to 4 percent of lubricant; 0.5 to 10 percent of active agent; 1 to 4 percent of dispersant; 80% -94% of deionized water; pH regulators: 0.1 to 1 percent; the pH value of the grinding slurry is 6.5-11.5, the flow rate of the slurry is 2-3 ml/s, and the step 4 is carried out;

and 4, step 4: taking down the GaAs wafer tool arranged on the thinning clamp of the crystal orientation angle grinding equipment in the step 3, placing the GaAs wafer tool in an etching pot, pouring hot alkali liquor into the etching pot to heat and etch the GaAs wafer bonded on the surface of the tool, wherein the hot alkali liquor comprises the following components in percentage by volume: hydrogen peroxide 73-77%, concentrated sulfuric acid 2.8-5%, glacial acetic acid 6.7-10%, concentrated hydrochloric acid 8.5-11.5%, and the corrosion amount is about 10um, so as to obtain a GaAs wafer with the warpage of a cut wafer being 1-5 um, and entering the step 5;

and 5: and (4) taking out the tool which is obtained in the step (4) and bonded with the GaAs wafer after low corrosion treatment, cleaning the tool by ultrasonic cleaning equipment, putting the tool into a clamp again to precisely polish the GaAs wafer, and finally taking out the tool and drying the GaAs wafer by centrifugal drying equipment.

Example 1

The processing method for improving the strength of the GaAs wafer comprises the following steps:

step 1: selecting a bonding position according to the crystal orientation characteristics of a GaAs wafer, coating photoresist on the surface of the GaAs wafer, spraying an adhesive A on the photoresist, wherein the adhesive A is a hexamethyldisilane adhesive, placing a tool in a vacuum environment with the temperature of 135-150 ℃ and the vacuum degree of less than or equal to 1 x 10 < -2 > mbar, spraying an adhesive B on the surface of the tool, wherein the adhesive B is a glycol titanate adhesive, bonding the tool and the GaAs wafer by using the adhesive A and the adhesive B, cooling the tool bonded with the GaAs wafer to the room temperature of 20-24 ℃, and entering a step 2;

step 2: mounting the tool bonded with the GaAs wafer obtained in the step 2 on a thinning clamp of a cutting device, adjusting the cutting azimuth structure of the cutting device, cutting the bonding position of the tool wafer and the tool by adopting an inclined spraying cutting mode to change the requirement that the Bow value is a plus value, and entering a step 3;

and step 3: the tool bonded with the GaAs wafer is taken down from the thinning clamp of the cutting device, the tool bonded with the GaAs wafer is installed on the thinning clamp of the crystal orientation angle grinding equipment, the grinding disc bonded with the grinding cloth and the grinding slurry are adopted to grind the GaAs wafer, the grinding cloth adopts single crystal diamond grinding cloth with a nano artificial diamond coating on the surface, the grain diameter of diamond grains in the coating is 400 nm-600 nm, the rotating speed of the grinding disc is 120-180 r/min, and the grinding slurry comprises the following components: a lubricant, a surfactant, a dispersant, deionized water and a pH value regulator; the weight percentage is as follows: 0.5 to 4 percent of lubricant; 0.5 to 10 percent of active agent; 1 to 4 percent of dispersant; 80% -94% of deionized water; pH regulators: 0.1 to 1 percent; the pH value of the grinding slurry is 6.5-11.5, the flow rate of the slurry is 2-3 ml/s, and the step 4 is carried out;

and 4, step 4: taking down the GaAs wafer tool arranged on the thinning clamp of the crystal orientation angle grinding equipment in the step 3, placing the GaAs wafer tool in an etching pot, pouring hot alkali liquor into the etching pot to heat and etch the GaAs wafer bonded on the surface of the tool, wherein the hot alkali liquor comprises the following components in percentage by volume: hydrogen peroxide 73-77%, concentrated sulfuric acid 2.8-5%, glacial acetic acid 6.7-10%, concentrated hydrochloric acid 8.5-11.5%, and the corrosion amount is about 10um, so as to obtain a GaAs wafer with the warpage of a cut wafer being 1-5 um, and entering the step 5;

and 5: and (4) taking out the tool which is obtained in the step (4) and bonded with the GaAs wafer after low corrosion treatment, cleaning the tool by ultrasonic cleaning equipment, putting the tool into a clamp again to precisely polish the GaAs wafer, and finally taking out the tool and drying the GaAs wafer by centrifugal drying equipment.

Example 2

The GaAs wafer strength processing method comprises the following steps:

step 1: selecting a bonding position according to the crystal orientation characteristics of a GaAs wafer, coating photoresist on the surface of the GaAs wafer, spraying an adhesive A on the photoresist, wherein the adhesive A is a hexamethyldisilane adhesive, placing a tool in a vacuum environment with the temperature of 135-150 ℃ and the vacuum degree of less than or equal to 1 x 10 < -2 > mbar, spraying an adhesive B on the surface of the tool, wherein the adhesive B is a glycol titanate adhesive, bonding the tool and the GaAs wafer by using the adhesive A and the adhesive B, cooling the tool bonded with the GaAs wafer to the room temperature of 20-24 ℃, and entering a step 2;

step 2: mounting the tool bonded with the GaAs wafer obtained in the step (2) on a thinning clamp of a cutting device, adjusting a cutting azimuth structure of the cutting device, cutting the bonding position of the tool wafer and the tool, and entering a step (3);

and step 3: the tool bonded with the GaAs wafer is taken down from the thinning clamp of the cutting device, the tool bonded with the GaAs wafer is installed on the thinning clamp of the crystal orientation angle grinding equipment, the grinding disc bonded with the grinding cloth and the grinding slurry are adopted to grind the GaAs wafer, the grinding cloth adopts single crystal diamond grinding cloth with a nano artificial diamond coating on the surface, the grain diameter of diamond grains in the coating is 400 nm-600 nm, the rotating speed of the grinding disc is 120-180 r/min, and the grinding slurry comprises the following components: lubricant, surfactant, dispersant and deionized water; the weight percentage is as follows: 1% -3% of a lubricant; 0.5 to 10 percent of active agent; 1 to 4 percent of dispersant; 60% -80% of deionized water; the pH value of the grinding slurry is 6.5-11.5, the flow rate of the slurry is 1-2 ml/s, and the step 4 is carried out;

and 4, step 4: taking down the GaAs wafer tool arranged on the thinning clamp of the crystal orientation angle grinding equipment in the step 3, placing the GaAs wafer tool in an etching pot, pouring hot alkali liquor into the etching pot to heat and etch the GaAs wafer bonded on the surface of the tool, wherein the hot alkali liquor comprises the following components in percentage by volume: 77% -82% of hydrogen peroxide, 1.8% -3.5% of concentrated sulfuric acid, 4.7% -8% of glacial acetic acid and 6.5% -9.5% of concentrated hydrochloric acid, wherein the corrosion amount is about 10um, the GaAs wafer with the Bow value of 1-5 um is obtained, and the step 5 is carried out;

and 5: and (4) taking out the tool which is obtained in the step (4) and bonded with the GaAs wafer after low corrosion treatment, cleaning the tool by ultrasonic cleaning equipment, putting the tool into a clamp again to precisely polish the GaAs wafer, and finally taking out the tool and drying the GaAs wafer by centrifugal drying equipment.

The result of the detection

The strength of the wafer of example 1 treated according to the invention can be increased by 50% compared to the wafer of example 2.

The above embodiments are preferred embodiments of the present invention, but the present invention is not limited to the above embodiments, and any other changes, modifications, substitutions, combinations, and simplifications which do not depart from the spirit and principle of the present invention should be construed as equivalents thereof, and all such changes, modifications, substitutions, combinations, and simplifications are intended to be included in the scope of the present invention.