Operation/margin enhancement feature for surface-MEMS structure; sculpting raised address electrode

Patent metadata

Field	Value
Publication number	US-9864188-B2
Application number	US-201414531842-A
Country	US
Kind code	B2
Filing date	Nov 3, 2014
Priority date	Nov 3, 2014
Publication date	Jan 9, 2018
Grant date	Jan 9, 2018

Abstract

A method of forming a micro-electromechanical systems (MEMS) pixel, such as a DMD type pixel, by forming a substrate having a non-planar upper surface, and depositing a photoresist spacer layer upon the substrate. The spacer layer is exposed to a grey-scale lithographic mask to shape an upper surface of the spacer layer. A control member is formed upon the planarized spacer layer, and an image member is formed over the control member. The image member is configured to be positioned as a function of the control member to form a spatial light modulator (SLM). The spacer layer is planarized by masking a selected portion of the spacer layer with a grey-scale lithographic mask to remove binge in the selected portion.

First claim

What is claimed is:

1. A method comprising:
depositing a photoresist spacer layer upon a non-planar upper surface of a substrate;
exposing the photoresist spacer layer to a grey-scale lithographic mask to shape an upper surface of the photoresist spacer layer;
forming a control member upon the shaped upper surface of the photoresist spacer layer;
removing the photoresist spacer layer to form an air gap between the control member and the substrate; and
forming a positionable image member over the control member, the image member: being positionable as a function of an electrostatic field distributed by the control member; and having a light reflective surface configured as part of a spatial light modulator to form at least a portion of an image by modulating incident light.

2. The method as specified in claim 1 , wherein the upper surface of the photoresist spacer layer is planarized by exposing the photoresist spacer layer to the grey-scale lithographic mask.

3. The method as specified in claim 2 , further comprising masking a selected portion of the photoresist spacer layer.

4. The method as specified in claim 3 , further comprising removing undulations in the selected portion.

5. The method as specified in claim 2 , wherein the image member is substantially parallel to the substrate.

6. The method as specified in claim 5 , wherein the control member includes an electrode having an upper surface, and all of the upper surface of the electrode is substantially parallel to the substrate.

7. The method as specified in claim 1 , wherein the substrate includes memory configured to control the electrostatic field distributed by the control member.

8. The method as specified in claim 1 , wherein the light reflective surface is a light reflective upper surface of the image member.

9. The method as specified in claim 1 , wherein the image member is formed on a torsion hinge.

10. The method as specified in claim 1 , wherein the control member includes an electrode having an upper surface, and all of the upper surface of the electrode is substantially parallel to the substrate.

11. A method comprising:
depositing a spacer layer upon a non-planar upper surface of a substrate;
exposing the spacer layer to a grey-scale lithographic mask to remove undulations in an upper surface of the spacer layer;
after the exposing, forming a control member upon the upper surface of the spacer layer;
removing the spacer layer to form an air gap between the control member and the substrate; and
forming a positionable image member over the control member, the image member: being positionable as a function of an electrostatic field distributed by the control member; and having a light reflective surface configured as part of a spatial light modulator to form at least a portion of an image by modulating incident light.

12. The method as specified in claim 11 , wherein the upper surface of the spacer layer is planarized by exposing the spacer layer to the grey-scale lithographic mask.

13. The method as specified in claim 11 , wherein the image member is substantially parallel to the substrate.

14. The method as specified in claim 11 , wherein the substrate includes memory configured to control the electrostatic field distributed by the control member.

15. The method as specified in claim 11 , wherein the light reflective surface is a light reflective upper surface of the image member.

16. The method as specified in claim 11 , wherein the image member is formed on a torsion hinge.

17. The method as specified in claim 11 , wherein the control member includes an electrode having an upper surface, and all of the upper surface of the electrode is substantially parallel to the substrate.

18. A method comprising:
depositing a photoresist spacer layer upon a non-planar upper surface of a substrate including memory;
exposing the photoresist spacer layer to a grey-scale lithographic mask to planarize an upper surface of the photoresist spacer layer;
forming a control member upon the planarized upper surface of the photoresist spacer layer;
removing the photoresist spacer layer to form an air gap between the control member and the substrate; and
forming a positionable image member over the control member, the image member: being substantially parallel to the control member; and being positionable as a function of an electrostatic field distributed by the control member as a function of the memory; and having a light reflective surface configured as part of a spatial light modulator (SLM) to form at least a portion of an image by modulating incident light.

19. The method as specified in claim 18 , wherein the control member includes an electrode having an upper surface, and all of the upper surface of the electrode is substantially parallel to the substrate.

20. The method as specified in claim 18 , wherein the image member is formed on a torsion hinge, and wherein the light reflective surface is a light reflective upper surface of the image member.

Assignees

• Texas Instruments Inc

Inventors

• Oden Patrick I
• Baker James C
• Zheng Sandra
• Mcdonald William C
• Barron Lance W

Classifications

• G02B26/0841 Primary

  the reflecting element being moved or deformed by electrostatic means · CPC title

• B81B3/00

  Devices comprising flexible or deformable elements, e.g. comprising elastic tongues or membranes (B81B5/00 takes precedence) · CPC title

• B81C1/00198 Primary

  comprising elements which are movable in relation to each other, e.g. comprising slidable or rotatable elements · CPC title

• B81B3/0045

  Improve properties related to angular swinging, e.g. control resonance frequency · CPC title

• B81B2203/0154

  Torsion bars · CPC title