The systems and methods discussed herein relate to integrated fuse structures.
Conventional fluid ejection systems, such as inkjet printing systems, include a printhead, an ink supply that provides liquid ink to the printhead, and an electronic controller that controls the printhead. The printhead ejects ink drops through multiple nozzles (also referred to as orifices) toward a print medium, such as a sheet of paper, thereby printing onto the print medium. Typically, the multiple nozzles are arranged in one or more arrays such that properly sequenced ejection of ink from the nozzles causes characters or other images to be printed on the print medium as the printhead and the print medium are moved relative to one another.
Certain fluid ejection devices contain one or more fuses as part of an integrated programmable read-only memory (PROM). The PROM is programmed by blowing (also referred to as “burning”) one or more fuses contained in the PROM. The PROM can be programmed with a serial number associated with the fluid ejection device, a model number associated with the fluid ejection device, electrical calibration data, fluidic data, or other data.
It is desirable to provide a fluid ejection device having a structure that allows one or more fuses to be blown with reliable results during a fuse programming process. Also, it is desirable to have such fuse structures that have low likelihoods of undesired short circuits during normal operation.
In one embodiment, a device includes a first layer disposed adjacent a substrate. A second layer is disposed adjacent the first layer. A third layer is disposed adjacent the second layer and contains a gap. A fuse is electrically coupled to the third layer and is located proximate the gap in the third layer.
The systems and methods discussed herein are illustrated by way of example and not limitation in the figures of the accompanying drawings. Similar reference numbers are used throughout the figures to reference like components and/or features.
The systems and methods described herein provide a fluid ejection device and method of operation suitable for use with inkjet printing systems and other systems that utilize fluid ejection devices. Although particular examples described herein refer to inkjet printing devices and systems, the systems and methods discussed herein are applicable to any fluid ejection device or component.
Ink supply assembly 104 supplies ink to printhead assembly 102 and includes an ink reservoir 106 that stores ink. Ink flows from ink reservoir 106 to printhead assembly 102. Ink supply assembly 104 and printhead assembly 102 can form either a one-way ink delivery system or a recirculating ink delivery system. In a one-way ink delivery system, substantially all of the ink supplied to printhead assembly 102 is consumed during printing. In a recirculating ink delivery system, only a portion of the ink supplied to printhead assembly 102 is consumed during printing. Ink that is not consumed during printing is returned to ink supply assembly 104.
In one embodiment, printhead assembly 102 and ink supply assembly 104 are housed together in an inkjet cartridge or pen. In another embodiment, ink supply assembly 104 is separate from printhead assembly 102 and supplies ink to printhead assembly 102 through an interface connection, such as a supply tube. In either embodiment, ink reservoir 106 of ink supply assembly 104 may be removed, replaced, or refilled. In one embodiment, where printhead assembly 102 and ink supply assembly 104 are housed together in an inkjet cartridge, ink reservoir 106 includes a local reservoir located within the cartridge as well as a larger reservoir located separately from the cartridge. In this embodiment, the separate, larger reservoir serves to refill the local reservoir. The separate, larger reservoir and/or the local reservoir can be removed, replaced, or refilled.
Mounting assembly 108 positions printhead assembly 102 relative to media transport assembly 110. Media transport assembly 110 positions print medium 116 relative to printhead assembly 102. A print zone 118 is defined adjacent nozzles 114 in an area between printhead assembly 102 and print medium 116. In one embodiment, printhead assembly 102 is a scanning type printhead assembly. In this embodiment, mounting assembly 108 includes a carriage that moves printhead assembly 102 relative to media transport assembly 110 to scan print medium 116. In another embodiment, printhead assembly 102 is a non-scanning type printhead assembly. In this embodiment, mounting assembly 108 fixes printhead assembly 102 at a particular position relative to media transport assembly 110. Media transport assembly 110 positions printhead medium 116 relative to printhead assembly 102.
Electronic controller 112 communicates with printhead assembly 102, mounting assembly 108 and media transport assembly 110. Electronic controller 112 receives data 120 from a host system, such as a computer, and includes memory capable of temporarily storing data 120. Typically, data 120 is sent to inkjet printing system 100 along an electronic, infrared, optical, or other information transfer path. Data 120 represents, for example, a document and/or file to be printed. In one embodiment, data 120 forms a print job for inkjet printing system 100 and includes one or more print job commands and/or command parameters.
In a particular embodiment, electronic controller 112 provides control of printhead assembly 102 including timing control for ejection of ink drops from nozzles 114. Electronic controller 112 defines a pattern of ejected ink drops that form characters, symbols, and/or other graphics or images on print medium 116. Timing control and the pattern of ejected ink drops is determined by, for example, the print job commands and/or command parameters. In one embodiment, logic and drive circuitry forming a portion of electronic controller 112 is incorporated in an integrated circuit (IC) located on printhead assembly 102. In another embodiment, logic and drive circuitry is located off printhead assembly 102.
As discussed above, printhead assembly 102 includes one or more printheads that eject drops of ink. In operations, energy is applied to resistors or other energy-dissipating elements in the printhead, which transfers the energy to ink in one or more nozzles (or orifices) 114 in the printhead. This application of energy to the ink causes a portion of the ink to be ejected out of the nozzle 114 toward the print medium 116. As ink is ejected from the nozzle 14, additional ink is received into the nozzle from the ink supply assembly 104.
A top layer 202 shown in
The next layer is a metal layer 208, such as aluminum. Metal layer 208 has a gap in the middle of the layer that is filled with material from dielectric layer 206. Metal layer 208 may also be referred to as a feed trace layer. Adjacent the metal layer 208 is an electrically resistive layer 210 composed of TaAl (tantalum aluminum). Alternatively, resistive layer 210 may be composed of polysilicon, WSiN (tungsten silicon nitride), or another electrically conductive material that generates, during conduction, an appropriate amount of heat to eject fluids. The metal layer 208 is electrically coupled to the resistive layer 210 such that electrical current can flow between the metal layer and the resistive layer.
Adjacent the resistive layer 210 is another dielectric layer 212 made from SiO2. The next layer is yet another dielectric layer 214 composed of USG (undoped silicon glass) or BPSG (boron-phosphorous doped glass), both of which are a form of silicon oxide. Adjacent to dielectric layer 214 is a field oxide layer 216. Field oxide layer 216 may also be referred to as an “electrical isolation layer” or a “thermal isolation layer”. The last layer illustrated in
The actual fuse portion of
The fuse shown in
When attempting to blow the fuse shown in
The barrier layer hole increases the possibility that ink in the printhead, when the printhead is operational, will come in contact with the fuse. For example, ink may flow through the hole in the barrier layer, through the dielectric layer 206 (which was damaged due to the fuse blowing process) and come in contact with the previously blown fuse. This ink contact may cause a short-circuit, thereby causing the blown fuse to appear as a closed circuit (i.e., a fuse that has not been blown).
The structure shown in
The next layer is a metal layer 310, composed of a material such as aluminum. The metal layer 310 has a gap in the middle of the layer that is filled with material from dielectric layer 308. Adjacent the metal layer 310 is another dielectric layer 312 composed of, for example, USG or BPSG. This dielectric layer 312 has a gap in the middle of the layer that is filled with material from metal layer 310 and dielectric layer 308. Additionally, the dielectric layer 312 gap is partially filled with a fuse 318 (also referred to as a “fuse layer” or a “resistive layer”). Fuse 318 may also be referred to as a “fusible link”. In one embodiment, fuse 318 is composed of polysilicon doped with phosphorous. In alternate embodiments, fuse 318 may be composed of polysilicon doped with arsenic or boron. In other embodiments, fuse 318 may be composed of undoped polysilicon. In another embodiment, fuse 318 is composed of tantalum (Ta), tantalum aluminum (TaAl), or WSiN. In one embodiment, the material used in fuse 318 is typically different from the material used in resistive layer 210 of
The metal layer 310 is electrically coupled to the fuse 318 such that electrical current can flow between the metal layer and the fuse. As shown in
Adjacent the dielectric layer 312 is a field oxide layer 314 that provides electrical and thermal isolation between a substrate 316 and dielectric layer 312 where fuse 318 is located. Field oxide layer 314 may also be referred to as an “electrical isolation layer” or a “thermal isolation layer”. The last layer illustrated in
When the fuse 318 is a closed circuit (i.e., allowing electrical current to flow through the fuse), the fuse appears as shown in
The fuse 318 shown in
In one embodiment, the process of blowing fuse 318 includes applying an electrical voltage of 26 volts across the fuse until the fuse blows. Completion of the fuse blowing process can be determined, for example, by identifying a drop in the current flowing from the electrical source generating the 26 volts that are applied across the fuse. This drop in current flow indicates an open circuit caused by the blown fuse. In one embodiment, a polysilicon fuse doped with phosphorous will blow in approximately 30 microseconds with the application of 26 volts across the fuse. The voltage and the time required to blow a particular fuse may vary depending on various factors, such as the size, shape, position and composition of the particular fuse.
In the embodiment of
The structure shown in
The structure shown in
Process 500 continues by disposing a second dielectric layer on the metal layer (block 510). A barrier layer is then disposed on the second dielectric layer (block 512) and a nozzle layer is disposed on the barrier layer (block 514). Process 500 represents one example of a process for creating a fuse structure. In alternate embodiments, one or more operations may be omitted from process 500. Further, alternate embodiments may include one or more additional operations not shown in process 500.
As mentioned above, the fuse structure created by process 500 can be used in a printhead or other device. In other devices, one or more of the operations in process 500 may be omitted. For example, disposing a barrier layer (block 512) and disposing a nozzle layer (block 514) may not be necessary if the fuse structure is not intended for a fluid ejection device, such as a printhead. In other embodiments, different operations in process 500 may be omitted and/or other operations may be added.
In one embodiment, fuse 602 is composed of polysilicon doped with phosphorous and metal layer 604 is composed of aluminum. Fuse 602 may alternatively be composed of other materials, such as those discussed with respect to
Although particular examples of fuse structures have been discussed herein, alternate embodiments may include different configurations, arrangements, and positions of various layers and components (e.g., fuses) in the structure. For example, a fuse may be located above the gap in the metal layer, below the gap in the metal layer, or substantially coplanar with the gap in the metal layer. Further, the shape and/or size of the gap may vary as well as the shape and/or size of the fuse.
The systems and methods discussed herein are applicable to any type of printhead or other fluid ejection device. Further, these systems and methods can be applied to various types of fuses, fuse structures and related devices.
Although the description above uses language that is specific to structural features and/or methodological acts, it is to be understood that the method and apparatus for data reconstruction defined in the appended claims is not limited to the specific features or acts described. Rather, the specific features and acts are disclosed as exemplary forms of implementing the systems and methods described herein.
Number | Name | Date | Kind |
---|---|---|---|
3576549 | Hess et al. | Apr 1971 | A |
3803450 | Trogdon | Apr 1974 | A |
5363134 | Barbehenn et al. | Nov 1994 | A |
5389814 | Srikrishnan et al. | Feb 1995 | A |
5414245 | Hackleman | May 1995 | A |
5445694 | Gillner et al. | Aug 1995 | A |
5457059 | Keller et al. | Oct 1995 | A |
5469981 | Srikrishnan et al. | Nov 1995 | A |
5471163 | Childers | Nov 1995 | A |
5508724 | Boyd et al. | Apr 1996 | A |
5585662 | Ogawa | Dec 1996 | A |
5585663 | Bezama et al. | Dec 1996 | A |
5635968 | Bhaskar et al. | Jun 1997 | A |
5793095 | Harvey | Aug 1998 | A |
5813881 | Nathan et al. | Sep 1998 | A |
5827759 | Froehner | Oct 1998 | A |
5871826 | Mei et al. | Feb 1999 | A |
5923960 | Harvey | Jul 1999 | A |
6150916 | Lin et al. | Nov 2000 | A |
6161916 | Gibson et al. | Dec 2000 | A |
6162686 | Huang et al. | Dec 2000 | A |
6180503 | Tzeng et al. | Jan 2001 | B1 |
6197621 | Harvey | Mar 2001 | B1 |
6259146 | Giust et al. | Jul 2001 | B1 |
6288436 | Narayan et al. | Sep 2001 | B1 |
6306746 | Haley et al. | Oct 2001 | B1 |
6368902 | Kothandaraman et al. | Apr 2002 | B1 |
6390589 | Imanaka et al. | May 2002 | B1 |
6403403 | Mayer et al. | Jun 2002 | B1 |
6423582 | Fischer et al. | Jul 2002 | B1 |
6479308 | Eldridge | Nov 2002 | B1 |
6495901 | Brintzinger et al. | Dec 2002 | B2 |
6512284 | Schulte et al. | Jan 2003 | B2 |
6549690 | Schulte et al. | Apr 2003 | B2 |
6558969 | Miller et al. | May 2003 | B2 |
6559042 | Barth et al. | May 2003 | B2 |
6559973 | Bullock et al. | May 2003 | B2 |
6562674 | Tsuura | May 2003 | B1 |
6566730 | Giust et al. | May 2003 | B1 |
6567251 | Schulte et al. | May 2003 | B1 |
20030025177 | Kothandaraman | Feb 2003 | A1 |
20040085405 | Baek | May 2004 | A1 |
Number | Date | Country | |
---|---|---|---|
20050145982 A1 | Jul 2005 | US |