Electrical fuses with redundancy

• US 7,405,989 B2
• Filed: 03/07/2005
• Issued: 07/29/2008
• Est. Priority Date: 03/07/2005
• Status: Expired due to Fees

• Current Assignee: Taiwan Semiconductor Manufacturing Company Limited
• Original Assignee: Taiwan Semiconductor Manufacturing Company Limited
• Inventors: Chung, Shine Chien
• Primary Examiner(s): Nguyen; Viet Q
• Application Number:
  US11/074,920
• Publication Number:
  US 20060197178A1
• Time in Patent Office: 1,240 Days
• Field of Search: 365/225.7, 365/200, 365/230.06, 365/230.08, 365/230.01
• US Class Current: 365/225.7
• CPC Class Codes: G11C 17/14 in which contents are determined by selectively establishing, breaking or modifying connecting links by permanently altering the state of coupling elements, e.g. PROM
• CPC Class Codes: G11C 17/16 using electrically-fusible links
• CPC Class Codes: G11C 29/816 for an application-specific layout
• CPC Class Codes: G11C 29/846 by choosing redundant lines at an output stage
• CPC Class Codes: H01L 23/5256 comprising fuses, i.e. connections having their state changed from conductive to non-conductive
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00

Abstract

The present disclosure provides an electrical fuse cell with redundancy features and the method for operating the same. The fuse cell includes a first set of electrical fuses having at least one electrical fuse contained therein, and a second set of electrical fuses having at least one electrical fuse for providing redundancy to at least one fuse of the first set, wherein if one of the first set of electrical fuses is defective, at least one of the second set of the electrical fuses can be programmed to provide a redundancy function of the defective fuse.

Claims

1. An electrical fuse cell with redundancy features comprising:

a first set of electrical fuses having at least one electrical fuse contained therein;

a second set of electrical fuses having at least one electrical fuse for providing redundancy to the first set;

an address buffer for providing an address for accessing at least one fuse of the first set;

a first decoder for locating the fuse of the first set to be accessed based on the address provided by the address buffer;

a match redundant address module for providing one or more addresses of defective fuses in the first set; and

a second decoder address for locating a redundant fuse from the second set for the fuse to be accessed in the first set based on the address provided by the address buffer,

wherein upon detecting that the fuse of the first set to be accessed is defective, the redundant fuse of the second set is accessed.

2. The cell of claim 1, wherein if the fuse to be accessed in the first set is defective, a signal is generated to disable the first decoder.

3. The cell of claim 1 further comprising a selection module for selectively generating an output based on the fuse accessed either in the first set or the second set.

4. The cell of claim 1 wherein the match redundant address module comprises electrical fuses to program defective addresses in the first set.