Method and apparatus for analyzing cuts

• US 6,192,289 B1
• Filed: 02/13/1998
• Issued: 02/20/2001
• Est. Priority Date: 04/13/1997
• Status: Expired due to Term

• Current Assignee: Camtek Limited (Hexagon AB)
• Original Assignee: Inspectech Ltd.
• Inventors: Geffen, Michael, Ben-Har, Abraham
• Primary Examiner(s): Grant, William
• Assistant Examiner(s): Bahta, Kidest
• Application Number:
  US09/023,558
• Time in Patent Office: 1,103 Days
• Field of Search: 700/121, 700/167, 700/173-177, 700/195, 700/163, 702/179, 702/182, 702/185, 702/81, 382/141, 382/129, 438/460, 438/462
• US Class Current: 700/121
• CPC Class Codes: G06T 2207/30148 Semiconductor; IC; Wafer
• CPC Class Codes: G06T 7/0004 Industrial image inspection
• CPC Class Codes: H01L 21/78 with subsequent division of the substrate into plural individual devices cutting to change the surface-physical characteristics or shape of semiconductor bodies H01L21/304

Abstract

A system for analyzing the quality of the sawing of a material which includes a scanning unit, a cut parameter identifier and a cut analyzer. The scanning unit scans along cuts of the material and views at least a portion of a cut. The cut parameter identifier identifies and stores parameters of the viewed cut portion. The cut analyzer analyzes the parameters of a multiplicity of viewed cut portions and which determines the quality of the cuts therefrom.

Claims

1. A system for analyzing the quality of the sawing of a material, the system comprising:

scanning means which scans along cuts of said material and which views at least a portion of a cut;

a cut parameter identifier which identifies and stores parameters of said viewed cut portion, said cut parameter identifier comprising;

a kerf identifier which identifies upper and lower kerfs of said viewed cut portion; and

a chip parameter identifier which identifies sawing chips along said upper and lower kerfs and determines parameters thereof; and

a cut analyzer which analyzes said parameters of a multiplicity of viewed cut portions and which determines the quality of said cuts therefrom.

2. A system according to claim 1 and wherein said chip parameters include at least one of the following parameters:

chip height, chip width, chip aspect ratio, chip penetration, chip roughness and chip slope.

3. A system according to claim 2 and wherein said chip parameter identifier includes means for identifying possible sawing chips, means for determining said chip parameters for said possible sawing chips and means for marking said possible sawing chips as sawing chips or as non-chip elements based on the values of said chip parameters.

4. A system according to claim 1 and wherein said cut analyzer comprises a cut parameter identifier which compares a center line of said viewed cut portion, defined by center lines of said upper and lower kerfs, to a center line of a street within which said cut occurred to produce at least one of the following cut parameters:

cut angle and cut offset.

5. A method of identifying sawing chips, the method comprising the steps of:

identifying upper and lower kerfs of a viewed cut section;

identifying possible sawing chips along said upper and lower kerfs;

determining chip parameters for each of said possible sawing chips; and

marking said possible sawing chips as sawing chips or as non-chips based on the values of said chip parameters.

6. A method according to claim 5 and wherein said chip parameters include at least one of the following parameters:

chip height, chip width, chip aspect ratio, chip penetration, chip roughness and chip slope.

7. A method according to claim 5 and wherein said step of marking includes the steps of associating a plurality of chip and non-chip membership values with said possible sawing chips based on the values of said chip parameters, summing said chip and non-chip membership values to produce membership sums and determining whether said possible sawing chip is a sawing chip based on said membership sums.