Method of multi-stage substrate etching and terahertz oscillator manufactured using the same method

• US 20090120903A1
• Filed: 03/04/2008
• Published: 05/14/2009
• Est. Priority Date: 11/09/2007
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Kim, Jong Seok, Hong, Seog Woo, Kim, Sun Il, Jun, Seong Chan, Baik, Chan Wook
• Granted Patent: US 8,293,124 B2
• Time in Patent Office: Days
• US Class Current: 216/33
• CPC Class Codes: B44C 1/227 by etching
• CPC Class Codes: H01L 2223/6627 Waveguides, e.g. microstrip line, strip line, coplanar line
• CPC Class Codes: H01L 23/66 High-frequency adaptations
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01L 2924/1903 including wave guides
• CPC Class Codes: H03B 28/00 Generation of oscillations by methods not covered by groups H03B5/00 - H03B27/00, including modification of the waveform to produce sinusoidal oscillations analogue function generators for performing computing operations G06G7/26; use of transformers for conversion of waveform in ac-ac converters H02M5/18

Abstract

A method of multi-stage substrate etching is provided. The method comprises the steps of: forming a first mask pattern on one surface of a first substrate; forming a hole by etching the first substrate using the first mask pattern as an etching mask; forming a second mask pattern on one surface of a second substrate; forming a hole by etching the second substrate to a predetermined depth using the second mask pattern as an etching mask; bonding the first and second substrates together such that an etched surface of the first substrate faces an etched surface of the second substrate; forming a third mask pattern on the second substrate; and forming a hole passing through the second substrate by etching the second substrate using the third mask pattern as an etching mask, whereby it is prevented the occurrence of a radius of curvature in the bottom surface and the overhang structure occurring on a step surface, so that etching quality is improved, a precise bonding between the substrates is obtained using the alignment key positioned on each substrate, and a multi-layer process is carried out.

Claims

1. A method of multi-stage substrate etching comprising the steps of:

forming a first mask pattern on one surface of a first substrate;

forming a hole by etching the first substrate using the first mask pattern as an etching mask;

forming a second mask pattern on one surface of a second substrate;

forming a hole by etching the second substrate to a predetermined depth using the second mask pattern as an etching mask;

bonding the first and second substrates together such that an etched surface of the first substrate faces an etched surface of the second substrate;

forming a third mask pattern on the second substrate; and

forming a hole passing through the second substrate by etching the second substrate using the third mask pattern as an etching mask.

2. The method of multi-stage substrate etching according to claim 1, wherein the predetermined depth is ½

or more times a thickness of the second substrate.

3. The method of multi-stage substrate etching according to claim 1, wherein the third mask pattern has the same pattern as the second mask pattern.

4. The method of multi-stage substrate etching according to claim 1, wherein the step of bonding the first and the second substrates comprises the steps of:

forming an oxide film on the second substrate; and

bonding the first substrate and the second substrate together using the oxide film of the second substrate.

5. The method of multi-stage substrate etching according to claim 1, wherein the step of bonding the first and the second substrates comprises the steps of:

forming a metal thin film on the first substrate;

forming a solder line pattern on the second substrate; and

eutectic-bonding the solder line pattern to the metal thin film.

6. The method of multi-stage substrate etching according to claim 1, wherein the step of forming the first mask pattern comprises the steps of:

forming an oxide film of the first substrate;

forming a photo resist (PR) coating on one surface of the first substrate having the oxide film, and forming an alignment key pattern on the PR coated surface; and

forming the first mask pattern on the surface opposite to the PR coated surface.

7. The method of multi-stage substrate etching according to claim 6, wherein the step of bonding the first and the second substrates comprises the step of arranging the first substrate and the second substrate using the alignment key pattern.

8. A terahertz oscillator manufactured by a multi-stage substrate etching method and comprising two or more structures bonded together,

wherein the method comprises the steps of:

forming a first mask pattern on one surface of a first substrate and forming a hole by etching the first substrate using the first mask pattern as an etching mask;

forming a second mask pattern on one surface of a second substrate and forming a hole by etching the second substrate to a predetermined depth using the second mask pattern as an etching mask;

bonding the first and second substrates together such that an etched surface of the first substrate faces an etched surface of the second substrate; and

forming a third mask pattern on the second substrate and forming a hole passing through the second substrate by etching the second substrate using the third mask pattern as an etching mask.

9. The terahertz oscillator according to claim 8, wherein the step of forming a hole by etching the first substrate comprises the step of forming a photo resist (PR) coating on one surface of the first substrate, and forming an alignment key pattern on the PR coated surface.

10. The terahertz oscillator according to claim 9, wherein the two or more structures are aligned with each other using the alignment key pattern formed on each structure, and wherein the two or more structures are bonded together using Si direct bonding or eutectic bonding.