Etchant and etching process for substrate of a semiconductor device

Patent metadata

Field	Value
Publication number	US-10353147-B2
Application number	US-201615339446-A
Country	US
Kind code	B2
Filing date	Oct 31, 2016
Priority date	Jan 24, 2013
Publication date	Jul 16, 2019
Grant date	Jul 16, 2019

Abstract

A system and method for manufacturing semiconductor devices is provided. An embodiment comprises using an etchant to remove a portion of a substrate to form an opening with a 45° angle with a major surface of the substrate. The etchant comprises a base, a surfactant, and an oxidant. The oxidant may be hydrogen peroxide.

First claim

What is claimed is:

1. A semiconductor device comprising:
an optical bench substrate;
an opening in the optical bench substrate, the opening having a bottom and side surfaces and having an angle of about 45° from a major surface of the optical bench substrate and having a bottom surface free from etching hillocks at least within a region having a width of about 50 μm;
a reflective material covering the bottom and side surfaces of the opening from a first side of the opening to a second side of the opening opposite the first side; and
a waveguide located within the opening.

2. The semiconductor device of claim 1 , further comprising a core material located within the opening.

3. The semiconductor device of claim 2 , further comprising a cladding material located within the opening.

4. The semiconductor device of claim 3 , wherein the core material has a refractive index higher than the cladding material.

5. The semiconductor device of claim 1 , further comprising a through via extending from a first side of the optical bench substrate to a second side of the optical bench substrate opposite the first side.

6. A semiconductor device comprising:
an optical bench substrate;
an opening for a reflective material in the optical bench substrate, the opening having a sidewall with an angle of about 45° from a major surface of the optical bench substrate;
an etchant within the opening, the etchant comprising:
a base at a concentration of between about 25%-wt and about 35%-wt;
a surfactant at a concentration of between about 0.01%-wt and about 0.4%-wt; and
an oxidant at a concentration of between about 0.1%-wt and about 0.2%-wt.

7. The semiconductor device of claim 6 , wherein the oxidant is H 2 O 2 .

8. The semiconductor device of claim 6 , wherein the oxidant is ozone.

9. The semiconductor device of claim 6 , wherein the oxidant is KMnO 4 .

10. The semiconductor device of claim 6 , wherein the base comprises KOH and the oxidant comprises H 2 O 2 .

11. The semiconductor device of claim 6 , wherein the surfactant comprises a sulfonate base.

12. A semiconductor device comprising:
a semiconductor substrate; and
an opening in the semiconductor substrate;
an etchant within the opening, the etchant comprising:
a base for removing material from a waveguide substrate covered with a patterned hardmask, the base having a concentration of between 25%-wt and about 35%-wt;
a surfactant for modifying an angle of etching to about 45° from a major surface of the waveguide substrate, the surfactant reactable on the waveguide substrate to form an oil by-product, the surfactant having a concentration of between about 0.01%-wt and about 0.4%-wt; and
an oxidant for oxidizing the waveguide substrate beneath the oil by-product, the oxidant having a concentration of between about 0.1%-wt and about 0.2%-wt.

13. The semiconductor device of claim 12 , wherein the oxidant is H 2 O 2 .

14. The semiconductor device of claim 12 , wherein the oxidant is ozone.

15. The semiconductor device of claim 12 , wherein the oxidant is KMnO 4 .

16. The semiconductor device of claim 12 , wherein the base comprises KOH and the oxidant comprises H 2 O 2 .

17. The semiconductor device of claim 12 , wherein the base comprises KOH and the oxidant comprises H 2 O 2 .

18. The semiconductor device of claim 17 , wherein the surfactant comprises a sulfonate base.

19. The semiconductor device of claim 17 , wherein the surfactant comprises alkyl polysaccharide.

20. The semiconductor device of claim 1 , further comprising a through via extending through the optical bench substrate.

Assignees

• Taiwan Semiconductor Mfg Co Ltd

Inventors

• Lee Wan-Yu
• Kuo Ying-Hao
• Chen Hai-Ching
• Bao Tien-I

Classifications

• H10P50/694

  characterised by their behaviour during the process, e.g. soluble masks or redeposited masks · CPC title

• H10P50/644 Primary

  Anisotropic liquid etching (H10P50/61 takes precedence) · CPC title

• H10P50/642

  Chemical etching · CPC title

• C09K13/02

  containing an alkali metal hydroxide · CPC title

• G02B6/42

  Coupling light guides with opto-electronic elements · CPC title