Mask blank and phase shift mask using same

Patent metadata

Field	Value
Publication number	US-10444619-B2
Application number	US-201715641454-A
Country	US
Kind code	B2
Filing date	Jul 5, 2017
Priority date	Jul 26, 2016
Publication date	Oct 15, 2019
Grant date	Oct 15, 2019

Abstract

A mask blank includes: a light transmitting substrate; a first layer disposed on the light transmitting substrate, and including a chromium compound that contains chromium and at least one element selected from oxygen, nitrogen, and carbon; and a second layer disposed on the first layer as an outermost layer from among the first and second layers, and including a silicon compound that contains silicon and at least one element selected from oxygen, nitrogen, and carbon, an alloy of a transition metal and silicon, or a transition metal and silicon compound that contains a transition metal, silicon, and at least one element selected from oxygen, nitrogen, and carbon. The thickness of the first layer is 45 nm or less, and the thickness of the second layer is 5 nm or greater. An optical density of a stack composed of the first layer and the second layer is 3 or greater.

First claim

What is claimed is:

1. A mask blank comprising:
a light transmitting substrate;
a first layer disposed on the light transmitting substrate, and including a chromium compound that contains chromium and at least one element selected from oxygen, nitrogen, and carbon; and
a second layer disposed on the first layer as an outermost layer, and including a nitride that contains molybdenum and silicon,
wherein an optical density (OD) of a stack composed of the first layer and the second layer is 3 or greater.

2. The mask blank of claim 1 ,
wherein the thickness of the first layer is 45 nm or less, and the thickness of the second layer is 5 nm or greater.

3. The mask blank of claim 2 ,
wherein the thickness of the first layer is about 30 nm or less, and the thickness of the second layer is a value ranging from about 10 nm to about 40 nm.

4. The mask blank of claim 1 ,
wherein the second layer comprises a material having characteristics of being dry etched along with the light transmitting substrate.

5. The mask blank of claim 1 ,
wherein the second layer and the light transmitting substrate comprise at least one element in common.

6. The mask blank of claim 1 ,
wherein the light transmitting substrate does not comprise an etching stop layer having an etching selectivity with respect to the light transmitting substrate.

7. The mask blank of claim 1 ,
wherein the light transmitting substrate is a quartz substrate, and the first layer is composed of material selected from a chromium nitride (CrN), a chromium oxynitride (CrON), and a chromium oxycarbide (CrCO).

Assignees

• Samsung Electronics Co Ltd

Inventors

• Lee Hye Kyoung
• Jang Il Yong
• Seo Hwan Seok
• Kim Byung Gook

Classifications

• H10P76/4085

  characterised by the processes involved to create the masks · CPC title

• H10P76/2041

  Photolithographic processes · CPC title

• G03F1/32 Primary

  Attenuating PSM [att-PSM], e.g. halftone PSM or PSM having semi-transparent phase shift portion,; Preparation thereof · CPC title

• G03F1/58

  having two or more different absorber layers, e.g. stacked multilayer absorbers · CPC title

• G03F7/001

  Phase modulating patterns, e.g. refractive index patterns · CPC title