CN1569396A - Grind process for optical sapphire crystal substrate - Google Patents

Abstract

The invention discloses a grinding process for optical sapphire crystal basal piece. It includes steps of coarse grind, precise grind and polishing. The one time qualification rate is more than 98.5%, the surface coarse is less than 0.3 nanometer, the flatness rate is less than 5 micrometer, the flatness is minus and plus 0.025 millimeters, the thickness size difference is less than plus and minus 0.025 millimeters.

Description

The grinding technics of optics sapphire crystal substrate

Technical field

The present invention relates to a kind of technology of twin grinding optical grade sapphire crystal substrate.

Background technology

Optics sapphire crystal substrate is as blue LED, it is desirable GaN base backing material, it is the key component of semiconductor components and devices, the processing that subject matter is substrate of present domestic optical grade sapphire substrate development, because the ratio of the external diameter of this substrate and thickness is below 100: 0.5, the ratio of normal routine is 100: 10, and size is φ 2 " more than (φ 2 " ≈ φ 50.80mm * 0.43mm), and is very high to the requirement of equipment and technology.The first-time qualification rate of the finished product that the grinding technics of the optics sapphire crystal substrate of prior art obtains is low, and surface roughness flatness, the smooth depth of parallelism, thickness dimensional tolerance etc. all can not adapt to the requirement as GaN base backing material well.

Summary of the invention

The grinding technics that the purpose of this invention is to provide a kind of optical grade sapphire crystal substrate, this technology not only can satisfy the processing request of sapphire crystal substrate, and technology is simple, can effectively cut down finished cost.

For achieving the above object, the grinding of optics sapphire crystal substrate provided by the invention comprises following processing step successively:

(1) corase grind: mix as lapping liquid with water according to the ratio of 30-50% with 13-16 diamond dust, middle employing glass mat is made element and is isolated grinding up and down mutually, adopts general emery disc as abrasive disk, and rotating speed is controlled at 300-600 rev/min, up and down to mill;

(2) finish grind: mix with water according to the ratio of 30-50% with 2-9 diamond dust and make lapping liquid, the middle division board that adopts the identical glass mat of corase grind to make element, rotating speed are controlled at 300-600 rev/min up and down to mill, and emery disc is identical with the emery disc of roughly grinding usefulness;

(3) polishing: use diamond polishing liquid, on the abrasive disk, the intermediate isolating plate was identical in the glass mat of corase grind correct grinding about polishing disk employing diamond polishing skin sticked at, and rotating speed is controlled at 350-600 rev/min, temperature is controlled between 25-45 ℃, finishes polishing process on polishing machine.

Sapphire crystal substrate according to grinding technics acquisition of the present invention, first-time qualification rate is greater than 98.5%, and the surface roughness of substrate is less than 0.3 nanometer, and flatness is less than 5 microns, the smooth depth of parallelism is ± 0.025 millimeter, and the thickness dimensional tolerance is less than ± 0.025 millimeter.

The specific embodiment

Below in conjunction with embodiment the grinding technics of sapphire crystal substrate of the present invention is further described.

Embodiment 1

(1) adopt No. 13 diamond dust to mix as lapping liquid with water according to 30% ratio, middle employing glass mat is made element and is isolated grinding up and down mutually, adopts general emery disc as abrasive disk, and rotating speed is controlled at 300 rev/mins, up and down to mill;

(2) finish grind: mix with water according to 30% ratio with No. 2 diamond dust and make lapping liquid, the middle division board that adopts the identical glass mat of corase grind to make element, rotating speed are controlled at 300 rev/mins up and down to mill, and emery disc is identical with the emery disc of roughly grinding usefulness;

(3) polishing: use diamond polishing liquid, on the abrasive disk, the intermediate isolating plate was identical in the glass mat of corase grind correct grinding about polishing disk employing diamond polishing skin sticked at, and rotating speed is controlled at 350 rev/mins, and temperature is controlled at 25 ℃, finishes polishing process on polishing machine.

According to the sapphire crystal substrate that the grinding technics of present embodiment obtains, first-time qualification rate is 98.5%, and the surface roughness of substrate is 0.3 nanometer, and flatness is 4 microns, and the smooth depth of parallelism is 0.025 millimeter, and the thickness dimensional tolerance is 0.025 millimeter.

Embodiment 2

(1) corase grind: mix as lapping liquid with water according to 50% ratio with No. 16 diamond dust, middle employing glass mat is made element and is isolated grinding up and down mutually, adopts general emery disc as abrasive disk, and rotating speed is controlled at 600 rev/mins, up and down to mill;

(2) finish grind: mix with water according to 50% ratio with No. 9 diamond dust and make lapping liquid, the middle division board that adopts the identical glass mat of corase grind to make element, rotating speed are controlled at 600 rev/mins up and down to mill, and emery disc is identical with the emery disc of roughly grinding usefulness;

(3) polishing: use diamond polishing liquid, on the abrasive disk, the intermediate isolating plate was identical in the glass mat of corase grind correct grinding about polishing disk employing diamond polishing skin sticked at, and rotating speed is controlled at 600 rev/mins, and temperature is controlled at 45 ℃, finishes polishing process on polishing machine.

According to the sapphire crystal substrate that the grinding technics of present embodiment obtains, first-time qualification rate is 99%, surface roughness 0.2 nanometer of substrate, and 3 microns of flatnesses, the smooth depth of parallelism are-0.025 millimeter, the thickness dimensional tolerance is 0.02 millimeter.

Embodiment 3

(1) corase grind: mix as lapping liquid with water according to 40% ratio with No. 14 diamond dust, middle employing glass mat is made element and is isolated grinding up and down mutually, adopts general emery disc as abrasive disk, and rotating speed is controlled at 450 rev/mins, up and down to mill;

(2) finish grind: mix with water according to 40% ratio with No. 6 diamond dust and make lapping liquid, the middle division board that adopts the identical glass mat of corase grind to make element, rotating speed are controlled at 450 rev/mins up and down to mill, and emery disc is identical with the emery disc of roughly grinding usefulness;

(3) polishing: use diamond polishing liquid, on the abrasive disk, the intermediate isolating plate was identical in the glass mat of corase grind correct grinding about polishing disk employing diamond polishing skin sticked at, and rotating speed is controlled at 500 rev/mins, and temperature is controlled at 35 ℃, finishes polishing process on polishing machine.

According to the sapphire crystal substrate that the grinding technics of present embodiment obtains, first-time qualification rate is 99.2%, and the surface roughness of substrate is 0.1 nanometer, and flatness is 5 microns, and the smooth depth of parallelism is 0.01 millimeter, 0.01 millimeter of thickness dimensional tolerance.

Embodiment 4

(1) corase grind: mix as lapping liquid with water according to 40% ratio with No. 15 diamond dust, middle employing glass mat is made element and is isolated grinding up and down mutually, adopts general emery disc as abrasive disk, and rotating speed is controlled at 400 rev/mins, up and down to mill;

(2) finish grind: mix with water according to 50% ratio with No. 4 diamond dust and make lapping liquid, the middle division board that adopts the identical glass mat of corase grind to make element, rotating speed are controlled at 500 rev/mins up and down to mill, and emery disc is identical with the emery disc of roughly grinding usefulness;

(3) polishing: use diamond polishing liquid, on the abrasive disk, the intermediate isolating plate was identical in the glass mat of corase grind correct grinding about polishing disk employing diamond polishing skin sticked at, and rotating speed is controlled at 400 rev/mins, and temperature is controlled at 30 ℃, finishes polishing process on polishing machine.

According to the sapphire crystal substrate that the grinding technics of present embodiment obtains, first-time qualification rate is for being 99.5%, and the surface roughness of substrate is 0.3 nanometer, and flatness is 4.5 microns, and the smooth depth of parallelism is-0.01 millimeter, and the thickness dimensional tolerance is-0.025 millimeter.

Embodiment 5

(1) corase grind: mix as lapping liquid with water according to 35% ratio with No. 16 diamond dust, middle employing glass mat is made element and is isolated grinding up and down mutually, adopts general emery disc as abrasive disk, and rotating speed is controlled at 550 rev/mins, up and down to mill;

(2) finish grind: mix with water according to 35% ratio with No. 8 diamond dust and make lapping liquid, the middle division board that adopts the identical glass mat of corase grind to make element, rotating speed are controlled at 350 rev/mins up and down to mill, and emery disc is identical with the emery disc of roughly grinding usefulness;

(3) polishing: use diamond polishing liquid, on the abrasive disk, the intermediate isolating plate was identical in the glass mat of corase grind correct grinding about polishing disk employing diamond polishing skin sticked at, and rotating speed is controlled at 400 rev/mins, and temperature is controlled at 40 ℃, finishes polishing process on polishing machine.

According to the sapphire crystal substrate that grinding technics of the present invention obtains, first-time qualification rate is 99.0%, and the surface roughness of substrate is 0.25 nanometer, and flatness is 5 microns, and the smooth depth of parallelism is 0.02 millimeter, and the thickness dimensional tolerance is 0.02 millimeter.

Claims (1)

1, a kind of grinding technics of optics sapphire crystal substrate comprises following processing step successively:

(1) corase grind: mix as lapping liquid with water according to the ratio of 30-50% with 13-16 diamond dust, middle employing glass mat is made element and is isolated grinding up and down mutually, adopts general emery disc as abrasive disk, and rotating speed is controlled at 300-600 rev/min, up and down to mill;

(2) finish grind: mix with water according to the ratio of 30-50% with 2-9 diamond dust and make lapping liquid, the middle division board that adopts the identical glass mat of corase grind to make element, rotating speed are controlled at 300-600 rev/min up and down to mill, and emery disc is identical with the emery disc of roughly grinding usefulness;

(3) polishing: use diamond polishing liquid, on the abrasive disk, the intermediate isolating plate was identical in the glass mat of corase grind correct grinding about polishing disk employing diamond polishing skin sticked at, and rotating speed is controlled at 350-600 rev/min, temperature is controlled between 25-45 ℃, finishes polishing process on polishing machine.