IP Library › Granted Patent US 12,713,866
Granted Patent B2
US 12,713,866 · App. 18/034,611 · Granted Aug 18, 2026

Equipment and process technologies for catalyst influenced chemical etching

Inventors: Sidlgata V. Sreenivasan (Austin, TX); Akhila Mallavarapu (Philadelphia, PA); Paras Ajay (Austin, TX)
Assignee: Board of Regents, The University of Texas System
H10P72/0424H10P50/642H10P50/644H10P72/0421H10B12/00H10D84/0158H10D84/038
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Quick Facts
Patent No.
US 12,713,866
App. No.
18/034,611
Granted
Aug 18, 2026
Kind
B2
Abstract

A method and system for etching a semiconductor substrate using catalyst influenced chemical etching. A group of independently controlled discrete actuators are configured to control a depth of an etch of a material on a substrate, where at least two of the group of independently controlled discrete actuators has distinct actuation values. Furthermore, the etch depth has a variation of less than 10% of a feature height across the substrate.

Claims (17)

1 . A method for preventing substantial collapse of high aspect ratio semiconducting structures by catalyst influenced chemical etching, the method comprising:

providing a semiconducting material;

patterning a catalyst layer on a surface of said semiconducting material, wherein said catalyst layer comprises a plurality of features, wherein unetched regions of a pattern adjacent to said plurality of features comprises collapse-avoiding features;

modifying catalytic activity of said patterned catalyst layer; and

exposing said modified patterned catalyst layer and said collapse-avoiding features to an etchant, wherein said patterned catalyst layer and said etchant cause etching of said semiconducting material to form fabricated structures corresponding to said plurality of features, wherein said collapse-avoiding features prevent substantial collapse of etched semiconducting material.

2 . A method for preventing substantial collapse of high aspect ratio nanostructures, the method comprising:

providing a substrate with material to be etched;

providing a patterned etch mask on said substrate; and

etching said material to be etched using said patterned etch mask, wherein a portion of said patterned etch mask prevents substantial collapse of said etched material;

wherein said etching is performed using catalyst influenced chemical etching using an activity-modified catalyst layer deposited on top of said patterned etch mask.

3 . A method for preventing substantial collapse of high aspect ratio nanostructures, the method comprising:

providing high aspect ratio nanostructures with collapse-avoiding caps;

depositing stabilizing material around a portion of said high aspect ratio nanostructures to bond with said collapse-avoiding caps forming a continuous ceiling of stabilizing material regions; and

removing said collapse-avoiding caps from regions other than said stabilizing material regions to expose said high aspect ratio nanostructures while said continuous ceiling remains supported by said stabilizing material regions.

4 . A method for preventing substantial collapse of high aspect ratio nanostructures, the method comprising:

providing high aspect ratio nanostructures with collapse-avoiding caps; and

bonding a pre-formed cover plate to said collapse-avoiding caps to create a continuous ceiling spanning across and supported by said high aspect ratio nanostructures, wherein said continuous ceiling and said high aspect ratio nanostructures define a plurality of enclosed or partially enclosed internal volumes.

Assignments (2)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jul 14, 2026
From: SREENIVASAN, SIDLGATA V.
To: BOARD OF REGENTS, THE UNIVERSITY OF TEXAS SYSTEM
Reel/Frame 075267/0055 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Apr 16, 2026
From: MALLAVARAPU, AKHILA; AJAY, PARAS
To: BOARD OF REGENTS, THE UNIVERSITY OF TEXAS SYSTEM
Reel/Frame 074392/0583 →
Continuity (2)
Provisional Application 63107354 · Oct 29, 2020
Related Publication 20230411178A1 · Dec 21, 2023
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