Information
-
Patent Grant
-
6764165
-
Patent Number
6,764,165
-
Date Filed
Monday, September 30, 200222 years ago
-
Date Issued
Tuesday, July 20, 200420 years ago
-
Inventors
-
Original Assignees
-
Examiners
-
CPC
-
US Classifications
Field of Search
US
- 347 63
- 347 64
- 347 49
- 347 50
- 347 87
-
International Classifications
-
Abstract
A mold configured to be coupled to a fluid ejection head die to allow a protective material to be molded around a plurality of contact pads on the die is disclosed. The mold includes a molding surface configured to cover the contact pads, wherein the molding surface is configured to support and shape the protective material during molding, and at least one side extending away from the molding surface, wherein the side is configured to contain the protective material during molding.
Description
BACKGROUND OF THE INVENTION
Fluid ejection devices may find uses in a variety of different technologies. For example, some printing devices, such as printers, copiers and fax machines, print by ejecting tiny droplets of a printing fluid from an array of fluid ejection mechanisms onto the printing medium. The fluid ejection mechanisms are typically formed on a fluid ejection head that is movably coupled to the body of the printing device. Careful control of the individual fluid ejection mechanisms, the movement of the fluid ejection head across the printing medium, and the movement of the medium through the device allow a desired image to be formed on the medium.
The fluid ejection mechanisms typically are fabricated on a semiconductor die that forms part of the fluid ejection head, and are controlled by control signals from off-printhead circuitry. To allow the control signals to reach the fluid ejection mechanisms, the fluid ejection die includes one or more electrical contacts for connecting the die to electrical connectors leading to the control circuitry. These contacts (or contact pads) are typically formed on the same surface of the die as the openings of the fluid ejection mechanisms.
Due to the proximity of the contact pads to the openings of the fluid ejection mechanisms on the die surface, it may be possible for fluid to contaminate the contact pad region of the fluid ejection head die during device use. This may cause electrical shorts to form between adjacent leads, and thus may degrade printhead performance.
SUMMARY OF THE INVENTION
The present invention provides a mold configured to be coupled to a fluid ejection head die to allow a protective material to be molded around a plurality of contact pads on the die. The mold includes a molding surface configured to cover the contact pads, wherein the molding surface is configured to support and shape the protective material during molding, and at least one side extending away from the molding surface, wherein the side is configured to contain the protective material during molding.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1
is an isometric view of a first embodiment of a fluid ejection device according to the present invention.
FIG. 2
is an isometric view of a fluid ejection cartridge of the embodiment of FIG.
1
.
FIG. 3
is a partially broken-away isometric view of a protective barrier of the fluid ejection cartridge of the embodiment of FIG.
1
.
FIG. 4
is an isometric view of a mold of the protective barrier of the embodiment of FIG.
1
.
FIG. 5
is a front perspective view of a die of the embodiment of FIG.
1
.
FIG. 6
is a magnified, partially-broken away isometric view of the mold and die of the embodiment of
FIG. 1
, with the encapsulant omitted for clarity.
FIG. 7
is a sectional view of the mold, die and encapsulant of the embodiment of FIG.
1
.
DETAILED DESCRIPTION
One embodiment of a fluid ejection device according to the present invention is shown generally at
10
in
FIG. 1
as a desktop printer. Fluid ejection device
10
includes a body
12
, and a fluid ejection cartridge
14
operatively coupled to the body. Cartridge
14
is configured to deposit a fluid onto a medium
16
positioned adjacent to the cartridge. Control circuitry in fluid ejection device
10
controls the movement of cartridge
14
across medium
16
, the movement of the medium under the cartridge, and the firing of individual fluid ejection mechanisms on the fluid ejection cartridge.
Although shown herein in the context of a printing device, a fluid ejection device according to the present invention may be used in any number of different applications. For example, a fluid ejection device according to the present invention may be used to eject an aerosol, or may find any of a number of uses in an analytical microfluidic system. Furthermore, while the depicted printing device takes the form of a desktop printer, a fluid ejection device according to the present invention may take the form of any other suitable type of printing device, and may have any other desired size, large- or small-format.
FIG. 2
shows the bottom of cartridge
14
in more detail. Cartridge
14
includes a cartridge body
20
configured to hold a volume of fluid, and a fluid ejection head
22
coupled to the cartridge body and configured to eject fluid onto medium
16
. An elongate electrical connector
24
is coupled with fluid ejection head
22
and a side of cartridge body
20
to allow fluid ejection head
22
to be connected to external control circuitry. Electrical connector
24
may take the form of a flexible ribbon circuit, and may include a plurality of individual conductive traces or wires to allow power to be provided separately to each fluid ejection mechanism. While fluid ejection head
22
is depicted in
FIG. 2
as being attached to cartridge
14
, it will be appreciated that a fluid ejection device according to the present invention may also have a fluid ejection head and a fluid supply positioned remotely from one another.
If left exposed, the connections between electrical connector
24
and fluid ejection head
22
may be susceptible to damage from such sources as electrical shorts caused by fluid contamination or fluid exposure of the leads, and mechanical damage caused by wiping structures commonly found in fluid ejection devices. Thus, fluid ejection device
10
also includes a protective barrier, indicated generally at
26
, disposed over selected portions of fluid ejection head
22
to cover and/or encapsulate the electrical connections between electrical connector
24
and fluid ejection head
22
.
FIG. 3
shows the structure of fluid ejection head
22
, electrical connector
24
and protective barrier
26
in more detail. Fluid ejection head
22
is formed by depositing thin films on a die
30
, which includes a fluid ejection region
32
having a plurality of fluid ejection mechanisms (not shown). Die
30
typically takes the form of a semiconductor substrate, but may be formed from any other suitable type of substrate as well. A plurality of electrical contacts
34
are formed on the fluid ejection head
22
and coupled to a plurality of electrical leads
36
, which are coupled to connector
24
. Electrical contacts
34
are connected to corresponding fluid ejection mechanisms, permitting power to be selectively provided to the individual fluid ejection mechanisms and enabling the controlled ejection of fluid.
Protective barrier
26
may include a plurality of features that combine to protect contacts
34
and leads
36
. For example, in one embodiment, protective barrier
26
includes a molded encapsulant
38
that extends over electrical contacts
34
, and may also include an outer barrier in the form of a preformed mold
40
used to mold encapsulant
38
. Encapsulant
38
is configured to encapsulate each contact
34
and associated leads
36
to electrically insulate each contact and associated lead from other contacts and leads. This may help to prevent damage from electrical shorts across the leads in the event of contamination by fluid, and also from mechanical features such as fluid ejection head wiping stations. Mold
40
also helps to protect contacts
34
and leads
36
from damage from wiping stations, and may protect encapsulant
38
from corrosion caused by the fluid, if the encapsulant material is susceptible to corrosion by the fluid.
Encapsulant
38
may be molded around contacts
34
and leads
36
by any suitable molding process. One example is as follows. First, mold
40
is positioned over a portion of cartridge
14
, as shown in
FIG. 2. A
bottom inside portion
43
of mold
40
may serve as a molding surface to contain and shape encapsulant
38
during the molding process. Bottom inside portion
43
of mold
40
typically includes an opening
44
positioned over fluid ejection region
32
of fluid ejection head
22
that allows fluid ejected by the fluid ejection mechanisms to reach the printing medium. Bottom inside portion
43
of mold
40
also may include a depression
42
formed in the region of the mold that covers contacts
34
and leads
36
to appropriately space the mold from the contacts and leads. On the outer surface of the mold, depression
42
is a protrusion over the area of the contacts
34
and the leads
36
. Mold
40
may also include an upturned side portion
45
to help contain encapsulant
38
during the molding process. In one embodiment, the side portion
45
extends to the cartridge body when the mold
40
is in place on the cartridge.
Mold
40
is placed over the bottom portion of cartridge
14
in such a manner that a space remains between the bottom of the cartridge and at least part of the bottom inside portion
43
of the mold. This spacing may be achieved in any desired manner. For example, the bottom portion
43
of mold
40
may curve away from the die as it extends away from opening
44
. Alternatively, in the depicted embodiment, mold
40
rests upon a plurality of raised structures situated around the perimeter of the die, as described in more detail below. In this manner, mold
40
may be quickly and easily positioned on die
30
to have the correct spacing with respect to the die.
After placing positioning mold
40
over the portion of cartridge
14
as depicted in
FIG. 2
, a curable, moldable encapsulant material is added to the mold and cured to form encapsulant
38
. The encapsulant material is typically added in a large enough quantity to fill the space between mold
40
and die
30
substantially completely. During the molding process, cartridge
14
is held in an orientation such that mold
40
and encapsulant
38
are positioned beneath fluid ejection head
22
, rotated 180 degrees from that depicted in FIG.
2
. This orientation may be referred to as an “upright” orientation for the purposes of explaining the depicted embodiment. After encapsulant
38
is cured, preformed mold
40
may be left adhered to cartridge
22
, or may be removed so that encapsulant
38
acts alone as protective barrier
26
.
The molding of encapsulant
38
over contacts
34
and leads
36
offers various advantages over other methods of forming a protective barrier around the contacts and leads. For example, a protective barrier could also be formed by first inverting cartridge
22
to the orientation shown in
FIG. 2
, and then applying a curable material over contacts
34
and leads
36
in liquid form via a syringe from above. However, this method of forming a protective barrier may pose some difficulties. For example, the rheology of curable material typically must be carefully controlled. While a low-viscosity curable material may fill the space between each contact and lead more quickly and thoroughly than a high-viscosity curable material, the low-viscosity curable material also may tend to run across the surface of the die too quickly, and thus may contaminate the openings of the fluid ejection mechanisms. Likewise, the use of a curable material with strong wetting properties may offer improved coverage of the leads and contacts, but also may have a higher risk of contaminating the fluid ejection mechanisms. Additionally, the speed of the application needle, the temperature of the application process and other environmental factors generally are matched to the rheology of the curable material, and carefully controlled during the encapsulation process. These environmental factors tend to change over time, so control of process may be changed dynamically.
In contrast, in some embodiments, the use of mold
40
allows materials of a wide variety of viscosities to be easily applied via a low-precision process while limiting the danger of the encapsulant material contaminating the fluid ejection mechanisms. When applied via the above-described technique, the encapsulant material is positioned underneath cartridge
14
during application and curing. Thus, the encapsulant material is less likely to run and contaminate undesired portions of fluid ejection head
22
than when the material is applied directly onto die
30
from above, as gravity tends to hold the encapsulant material within bottom inside portion
43
of mold
40
, whereas gravity tends to encourage the encapsulant material to wet the surface of the die when applied from above. Furthermore, as shown in
FIG. 7
, the inner edge of opening
44
of mold
40
may upon separators
48
that help to block the encapsulant from running towards the fluid ejection region
32
. These structures are described in more detail below.
Any suitable material may be used to form encapsulant
38
. As discussed above, the use of a curable liquid material with a relatively low viscosity may allow substantial coverage of all leads
34
and contacts
36
to be achieved more easily relative to a higher-viscosity encapsulant material. Furthermore, a low-viscosity material may flow into the spaces between leads
34
and contacts
36
more quickly than a high-viscosity material, and thus may help to decrease the amount of time to manufacture cartridge
14
. The material used to form encapsulant
38
may also be selected based upon other properties as well. For example, it may be selected to have sufficient elasticity to avoid fracturing due to the thermal expansion or contraction of die
30
, robustness to withstand repeated swipes over a fluid ejection head cleaning station commonly found in many fluid ejection devices, and/or chemical resistance to fluid corrosion. Suitable materials include, but are not limited to, epoxy materials. Examples of suitable epoxies include LOCTITE 3563, available from the Loctite Corporation, NAMICS CHIPCOAT, available from the Namics Corporation, and SIFEL 610, available from ShinEtsu Silicones of America.
In one embodiment, the material used to form encapsulant
38
may have any suitable pre-curing viscosity. Suitable pre-curing viscosities include dynamic viscosities within the range of between approximately 300 and 2500 centipoises, though viscosities outside of this range may also be used. Likewise, encapsulant
38
may have any suitable dimensions. For example, encapsulant
38
may have a thickness of 75-100 microns in the region of depression
42
. In the regions adjacent outside of depression
42
, encapsulant
38
may have the same thickness as the height of flow channel separators
48
, which are described in more detail below.
As mentioned above, mold
40
may be left on cartridge
14
after the encapsulant molding process to form part of protective barrier
26
. This may offer some advantages over removing mold
40
after completing the encapsulant molding process. For example, because mold
40
is not applied as a curable viscous material, it may potentially be made from a wider selection of materials than encapsulant
38
, some of which may have more favorable chemical and mechanical properties than the encapsulant material. One example of a suitable material for mold
40
is stainless steel. Stainless steel is resistant to corrosion caused by fluids, fracture from thermal expansion, and mechanical damage caused by fluid ejection head wiping stations, and is easily formed into the shape of mold
40
. Furthermore, the electrical conductivity of stainless steel does not affect contacts
34
and leads
36
, as the contacts and leads are electrically insulated from mold
40
by encapsulant
38
. Other suitable materials from which mold
40
may be formed include, but are not limited to, other metals, such as aluminum, and various polymer materials. Where mold
40
is left on cartridge
14
after the molding process, it may be adhered to the cartridge in any suitable manner. In some embodiments of the invention, mold
40
is adhered to cartridge
14
by the encapsulant after the encapsulant has cured.
The walls of mold
40
may have any suitable thickness. Where mold
40
is made from stainless steel foil, an exemplary range of thickness for mold
40
is between approximately 62 and 87 microns, although foils of thicknesses outside of this range may also be used. The use of a metal foil to form mold
40
offers the advantage that the mold may be easily constructed from a single piece of the foil by a simple forming process.
When mold
40
is left in place after the encapsulant molding process, a very small area between the edge of the mold and the die may remain unfilled by encapsulant
38
. Where this unfilled area exists, it may be possible for fluid to contaminate this area. To prevent this space from forming, or to prevent fluid from contaminating this space, either die
30
or mold
40
may include structure that permits the encapsulant material to flow into the region between edge
50
of the mold and the die to form a seal.
One suitable structure for permitting this seal to form is shown in
FIGS. 5 and 6
as a series of flow channels
46
formed in the surface of die
30
. Flow channels
46
are separated and/or defined by a plurality of flow channel separators
48
that take the form of raised areas between the flow channels. Flow channels
46
may act as capillary channels to wick encapsulant into the region of die
30
underneath the edge of mold
40
. Flow channels
46
may be formed on die
30
in any suitable manner, for example, by masking the regions of die
30
where flow channel separators
48
will be located (as well as other regions of the die that are not to be etched) with a photo-imageable material, and then etching the surface of the die. Alternatively, a series of flow channels may be formed in edge region
50
on bottom inner surface
43
of mold
40
, instead of in die
30
. Where the flow channels are formed in the surface of die
30
, as in the depicted embodiment, the flow channel separators may be formed from an oxide layer (or other electrically insulating layer) formed on the top surface of the die. If desired, an insulating strip
39
may also be formed along the edge of die
30
to further help to insulate leads
36
from the bulk of die
30
. Insulating strip
39
is located within encapsulated area, between leads
36
and die
30
, and between contacts
34
and edge of die
30
, along one side of die
30
. Insulating strip
39
may be formed by the same etching step as flow channels
46
, or may be formed via a separate processing step.
Flow channels
46
may have any suitable shape. The depicted flow channels
46
have an elongate shape, and each flow channel connects to adjacent flow channels at each end. However, the flow channels could also have a finger-like shape with only one open end, in which case flow channel separators
48
would connect at one end to fluid ejection region
32
of die
30
. Likewise, flow channels
46
may also have any suitable dimensions. Exemplary dimensional ranges include a depth of between approximately 20 and 35 microns, a length of between approximately 250 and 500 microns, and a width of between approximately 30 and 150 microns, though flow channels
46
may also have dimensions outside of these ranges.
FIGS. 6 and 7
show the junction between die
30
and mold
40
in more detail. The encapsulant is omitted from
FIG. 6
for clarity. Referring to
FIG. 6
, edge region
50
of mold
40
is configured to rest against the top surfaces of flow channel separators
48
. Because flow channel separators
48
extend above flow channels
46
, edge region
50
does not contact the bottom surfaces of flow channels
46
. Thus, the encapsulant material is free to flow through flow through channels
46
when added to mold
40
. Referring next to
FIG. 7
, a thin strip
52
of encapsulant
38
may be formed around edge region
50
from encapsulant material that flowed through flow channels
46
, thus helping to seal any small gaps that may exist between edge region
50
and the surface of die
30
. Selection of an encapsulant material with suitable wetting properties may help to prevent the encapsulant from wetting fluid ejection region
32
. After curing, encapsulant
38
covers an outer portion of connector
24
, and an inner portion of connector
24
between the connector and die
30
. In this embodiment, encapsulant
38
isolates each electrical contact from adjacent electrical contacts. Thus, the largest part of the outer surface of protective barrier
26
is formed by mold
40
, and only thin strip
52
of encapsulant
38
remains exposed where it seals the gap between edge region
50
and die
30
.
Although the present invention has been disclosed in specific embodiments thereof, the specific embodiments are not to be considered in a limiting sense, because numerous variations are possible. The subject matter of the invention includes all novel and nonobvious combinations and subcombinations of the various elements, features, functions, and/or properties disclosed herein. The following claims particularly point out certain combinations and subcombinations regarded as novel and nonobvious. These claims may refer to “an” element or “a first” element or the equivalent thereof. Such claims should be understood to include incorporation of one or more such elements, neither requiring nor excluding two or more such elements. Other combinations and subcombinations of features, functions, elements, and/or properties may be claimed through amendment of the present claims or through presentation of new claims in this or a related application. Such claims, whether broader, narrower, equal, or different in scope to the original claims, also are regarded as included within the subject matter of the invention of the present disclosure.
Claims
- 1. A cartridge, comprising:a body; a die coupled with the body, wherein the die has a fluid ejection mechanism and an electrical contact to the fluid ejection mechanism; an electrical connector extending along a side of the die and a side of the body, the electrical connector coupled with the electrical contact; a molded encapsulant covering the electrical contact, and at least a portion of the electrical connector; and a mold adhered to the molded encapsulant, wherein the mold includes an opening positioned over the fluid ejection mechanism to allow fluid ejected by the fluid ejection mechanism to reach the printing medium.
- 2. The cartridge of claim 1, wherein the mold includes an inner edge defining the opening, and wherein the inner edge surrounds the fluid election region of the die.
- 3. The cartridge of claim 1 wherein the mold is made of stainless steel.
- 4. The cartridge of claim 1 wherein the mold has a thickness of between approximately 62 and 87 microns.
- 5. The cartridge of claim 1, wherein the molded encapsulant is an epoxy adhesive.
- 6. The cartridge of claim 1, wherein the molded encapsulant is formed from a curable material with a pre-curing dynamic viscosity of between approximately 300 and 2500 centipoises.
- 7. A cartridge comprising:a body; a die coupled with the body, wherein the die has a fluid ejection mechanism and an electrical contact to the fluid ejection mechanism; an electrical connector extending along a side of the die and a side of the body, the electrical connector coupled with the electrical contact; and a molded encapsulant covering the electrical contact and at least a portion of the electrical connector, a mold having an edge region, wherein a plurality of flow channels are formed in the die to receive the molded encapsulant in a pre-cured state, wherein the flow channels are separated by a plurality of separators, and wherein the edge region of the mold contacts the separators such that molded encapsulant flows through the flow channels beneath the edge region of the mold during manufacturing.
- 8. The cartridge of claim 7, wherein molded encapsulant flows through the flow channels to form a strip of the molded encapsulant around the edge region of the mold.
- 9. The cartridge of claim 7, wherein the flow channels are etched into the die.
- 10. The cartridge of claim 7, wherein the flow channels have a depth of between approximately 20 and 35 microns.
- 11. The cartridge of claim 7, wherein the flow channels have a length of between approximately 250 and 500 microns.
- 12. The cartridge of claim 7, wherein the flow channels have a width of between approximately 30 and 150 microns.
- 13. A print cartridge, comprising:a printhead configured to eject a fluid onto a printing medium, wherein the printhead includes a die having an electrical contact and also includes a fluid election region having at least one fluid ejection mechanism configured to eject the fluid onto the printing medium; a connector coupled to the die for electrically connecting the die to off-printhead circuitry, the connector including a lead that is bonded to the electrical contact on the die; and a preformed barrier coupled with the die, wherein the preformed barrier covers the lead and the electrical contact to protect the lead and the electrical contact from the fluid, and wherein the preformed barrier includes an opening positioned over the fluid ejection region to allow fluid ejected by the fluid election mechanism to reach the printing medium.
- 14. The print cartridge of claim 13, wherein the opening is defined by an inner perimeter of the preformed barrier.
- 15. The print cartridge of claim 13, further comprising an encapsulant disposed between the preformed barrier and the die.
- 16. The print cartridge of claim 13, wherein the barrier is removable.
- 17. The print cartridge of claim 15, wherein at least a portion of the preformed barrier is separated from the die by a space, and wherein the encapsulant substantially completely fills the space between the portion of the preformed barrier and the die.
- 18. The printing cartridge of claim 13, wherein the barrier includes a raised portion disposed generally adjacent the electrical contact and the lead.
- 19. A print cartridge comprising:a printhead configured to eject a fluid onto a printing medium, wherein the printhead includes a die having an electrical contact, the die having a perimeter, wherein a plurality of flow channels are formed in the die adjacent the perimeter of the die to accommodate a fluid encapsulant material; a connector coupled to the die for electrically connecting the die to off-printhead circuitry, the connector including a lead that is bonded to the electrical contact on the die; and a preformed barrier coupled with the die, wherein the preformed barrier is configured to protect the lead and the electrical contact from the fluid.
- 20. The print cartridge of claim 19, wherein the flow channels are etched into the die.
- 21. The print cartridge of claim 19, wherein the flow channels are separated by a plurality of separators, and wherein the preformed barrier has an edge region in contact with the plurality of separators.
- 22. The print cartridge of claim 21, wherein a strip of encapsulant material is formed around the edge region of the preformed barrier.
- 23. A mold configured to be coupled to a fluid ejection head die to allow a protective material to be molded around a plurality of contact pads on the die, the fluid ejection head die including a fluid ejection mechanism configured to eject a fluid, the mold comprising:a molding surface configured to cover the contact pads, wherein the molding surface is configured to support and shape the protective material during molding; at least one side extending away from the molding surface, wherein the side is configured to contain the protective material during molding; and an opening configured to be positioned over the fluid ejection mechanism when the mold is coupled to the die to pass fluids ejected by the fluid ejection mechanism.
- 24. The mold of claim 23, wherein the mold is made of a material that is resistant to corrosion.
- 25. The mold of claim 23, wherein the mold is made of stainless steel.
- 26. The mold of claim 23, wherein the mold is formed from a single piece of material.
- 27. The mold of claim 23, wherein the mold includes a depression configured to accommodate the contact pads when the mold is coupled with the fluid ejection head die.
- 28. The mold of claim 23, wherein the opening includes is defined by an inner edge of the mold.
- 29. The mold of claim 23, wherein the mold is attached to a fluid ejection head.
- 30. A fluid ejection cartridge, comprising:a body; a fluid ejection head operably coupled with the body and including a fluid ejection mechanism configured to eject a fluid, wherein the fluid ejection head includes a die having an electrical contact; a connector electrically coupled to the contact on the die; and molded barrier means for protecting the electrical contact and at least part of the connector from the fluid, the molded barrier means including an opening positioned over the fluid ejection mechanism to bass fluids ejected by the fluid ejection mechanism.
- 31. A method for protecting an electrical connection of a lead and a contact pad on a die in a fluid ejection head, the method comprising:coupling a preformed mold with the die such that the preformed mold is positioned adjacent to and spaced from the electrical contact; adding a moldable protective material between the preformed mold and the electrical contact; and removing the preformed mold after curing the moldable protective material.
- 32. A method for protecting an electrical connection of a lead and a contact pad on a die in a fluid ejection head, the fluid ejection head having a fluid ejection mechanism, the method comprising:coupling a preformed mold with the die such that the preformed mold is positioned adjacent to and spaced from the electrical contact, and such that an opening in the preformed mold is positioned over the fluid ejection mechanism; and adding a moldable protective material between the preformed mold and the electrical contact.
- 33. The method of claim 32, wherein the preformed mold includes a raised area positioned adjacent the lead and contact before the moldable protective material is added.
- 34. The method of claim 32, wherein the moldable protective material is added in a fluid form.
- 35. The method of claim 32, further comprising curing the moldable protective material after adding the moldable protective material between the preformed mold and the electrical contact.
- 36. The method of claim 32, wherein the preformed mold remains bonded to the die by the moldable protective material.
- 37. The method of claim 32, wherein the moldable protective material is an epoxy adhesive.
- 38. The method of claim 32, wherein the moldable protective material has a pre-curing viscosity of between approximately 300 and 2500 centipoises.
- 39. A method for protecting an electrical connection of a lead and a contact pad on a die in a fluid ejection head, the method comprising:coupling a preformed mold with the die such that the preformed mold is positioned adjacent to and spaced from the electrical contact; and adding a moldable protective material between the preformed mold and the electrical contact, wherein the die includes a plurality of recessed flow channels, and wherein the mold is configured to rest against the die above the flow channels so that moldable protective material flows through the flow channels and beneath the mold during molding.
US Referenced Citations (10)