Etch

 

Description: Basic overview of etching to include wet and dry etch methods used in semiconductor manufacturing processes. Includes a focus on material, equipment, and etch quality.

Length of Time: 9 hrs

Prerequisites:

Module: Photolithography

Topics:

1. Definition of etch

2. Wet etch

Methods

Materials

Equipment

Attributes

3. Dry etch

Methods

Materials

Equipment

Attributes

Special resist considerations

4. Etch inspection

5. The future

 

Student Objectives:

Student will be able to:

1. Define "etch" and explain its use in semiconductor manufacturing process.

2. Discuss the quality of etch with reference to completeness, overcutting, undercutting, and selectivity. Explain what is meant by anisotropic etch and isotropic etch.

3. Compare and contrast wet etch with dry etch. Address relative strengths and weaknesses where appropriate.

4. List at least five types of wet etch used in semiconductor manufacturing process. Explain when each type would be used and list the chemicals, materials, and equipment necessary.

5. List at least five types of dry etch used in semiconductor manufacturing process. Explain when each type would be used and list the chemicals, materials, and equipment necessary. Define "plasma" and "ion beam" as related to dry etch.

6. Discuss special considerations concerning the thickness and thermal properties of resists in dry etch processes.

7. Show after-etch defects and give causes and prevention strategies for each.

8. Provide an overview of special equipment used in etch systems.

9. Put special attention on dry etch systems using plasma and ion beams. Include measurement and safety considerations.

10. Discuss future directions in etching and etch requirements.