PLANARIZING METHOD

• US 20090039056A1
• Filed: 08/10/2007
• Published: 02/12/2009
• Est. Priority Date: 08/10/2007
• Status: Active Grant

• Current Assignee: TDK Corporation
• Original Assignee: TDK Corporation
• Inventors: YATSU, Hideyuki, HATATE, Hitoshi, KAMIJIMA, Akifumi
• Granted Patent: US 7,862,737 B2
• Time in Patent Office: Days
• US Class Current: 216/38
• CPC Class Codes: G03F 7/00 Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor using photoresist structures for special production processes, see the relevant places, e.g. B44C, H01L, e.g. H01L21/00, H05K
• CPC Class Codes: G03F 7/2026 for the removal of unwanted material, e.g. image or background correction
• CPC Class Codes: G11B 5/3163 Fabrication methods or processes specially adapted for a particular head structure, e.g. using base layers for electroplating, using functional layers for masking, using energy or particle beams for shaping the structure or modifying the properties of the basic layers

Abstract

Provided is a planarizing method in which a planarization with high flatness can be performed, without being restricted by the distribution of film thickness in the applied resist film. The planarizing method comprises the steps of: forming a resist film on a film to be planarized formed on a substrate; exposing the resist film with the amounts of exposure light in respective sections into which an area in which the film to be planarized is formed is divided, the amounts of exposure light being determined so as to realize film thicknesses to be left for planarization of the resist film in the respective sections; developing the exposed resist film, to form a resist film pattern with a controlled distribution of film thickness; and etching the resist film pattern and the film to be planarized, until eliminating the thickness amounts to be eliminated of the film to be planarized.

Claims

1. A planarizing method comprising the steps of:

forming a resist film on a film to be planarized formed on a substrate;

exposing said resist film with the amounts of exposure light in respective sections into which an area is divided, said area being a region in which said film to be planarized is formed, said amounts of exposure light being determined so as to realize film thicknesses to be left for planarization of said resist film in the respective sections;

developing the exposed resist film, to form a resist film pattern with a controlled distribution of film thickness; and

etching said resist film pattern and said film to be planarized, until eliminating the thickness amounts to be eliminated of said film to be planarized.

2. The planarizing method as claimed in claim 1, wherein said film thicknesses to be left of said resist film are determined from said thickness amounts to be eliminated of said film to be planarized in the respective sections.

3. The planarizing method as claimed in claim 2, wherein:

an intended film thickness after planarization of said film to be planarized is set;

a total etching time required to obtain said intended film thickness after planarization is determined in a section including a portion with the smallest film thickness in said film to be planarized;

times required to etch said resist film in said section including the portion with the smallest film thickness and the other sections are determined from said total etching time; and

then, said film thicknesses to be left of said resist film are obtained.

4. The planarizing method as claimed in claim 1, wherein an area on which said resist film is formed is divided into sections each of which has a size equivalent to that of a window of a stepper, and then, the exposure in each of said sections is performed by using said stepper.

5. The planarizing method as claimed in claim 1, wherein the exposure in each of the sections is performed by using a gray-tone mask or a half-tone mask which realizes the required amounts of exposure light in the respective sections at one time.

6. The planarizing method as claimed in claim 1, wherein an ion milling method is used for the etching step.