Matrix of lid assemblies for electronic packages

Abstract

A method of making a matrix comprising a plurality of lid assemblies, the method comprising mating to a package lid material a solder preform mesh, comprising solder material and defining openings to form the plurality of lid assemblies wherein each lid assembly comprises a portion of the package lid material and a portion of the solder preform mesh to form a solder seal ring surrounding a respective opening. Alternatively, the solder comprises a solid solder preform. The lid assemblies achieve a hermetic seal that withstand gross leak to fine leak levels as measured by Mil-Std 883.

Description

MATRIX OF LID ASSEMBLIES FOR ELECTRONIC PACKAGESCROSS REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to U.S. Provisional Application No. 63 / 659,993, filed on June 14, 2024, which is incorporated herein by reference.FIELD

[0002] The present disclosure relates to a method of making a matrix comprising a plurality of lid assemblies in which a package lid material is mated to a solder preform mesh or a solid solder preform.BACKGROUND

[0003] Some hermetically sealed packages and methods of sealing are known. For example, WO / 2016106272 A1 discloses various embodiments of a hermetically sealed package and methods of forming such packages. In one or more embodiments, the hermetically sealed package can include a housing and a feedthrough assembly that forms a part of the housing. The feedthrough assembly can include a non-conductive substrate and a feedthrough. The feedthrough can include a via from an outer surface to an inner surface of the non-conductive substrate, a conductive material disposed in the via, and an external contact disposed over the via on the outer surface of the non-conductive substrate. The external contact can be electrically coupled to the conductive material disposed in the via. Further, the external contact can be hermetically sealed to the outer surface of the non-conductive substrate by a laser bond.

[0004] US 8,633,574 B2 discloses organic electronic packages having sealed edges. More specifically, packages having organic electronic devices are provided. A number of sealing mechanisms are provided to hermetically seal the edges of the package to completely protect the organic electronic device from external elements. A sealant may be implemented to completely surround the organic electronic device. Alternatively, edge wraps may be provided to completely surround the organic electronic device.

[0005] US 9,953,684 B2 discloses a method of assembling a data storage device which comprises forming an enclosure by overlapping each of a plurality of sidewalls of a cover with a corresponding sidewall of a base part, dispensing a liquid adhesive between the respective sidewalls of the cover and base part in such a quantity at each of a plurality of locations to promote capillary flow of the liquid adhesive to form a continuous film of liquid adhesive between the sidewalls, and curing the continuous film of liquid adhesive to form a hermetic seal between the cover and the base part. Embodiments may include surface treating the sidewall surface(s), which can help to promote the capillary flow of the liquid adhesive. The hermetic seal provides for a lighter-than-air gas to be held therein.

[0006] US 11 ,049,777 B2 discloses a frame lid for use with a semiconductor package is disclosed. First, a mask is applied to a top surface of the lid and over a central area of the top surface to define a peripheral area. Next, a seal ring is formed by metallizing the peripheral area and the sidewall of the plate. The mask can then be removed obtain the frame lid. Next, a solder preform can be attached to the seal ring. This reduces pullback and shrinkage of the metallized layer, while lowering the manufacturing cost and process times.

[0007] US 10,211 ,115 B2 discloses a frame lid for use with a semiconductor package. First, a mask is applied to a top surface of the lid and over a central area of the top surface to define a peripheral area. Next, a seal ring is formed by metallizing the peripheral area and the sidewall of the plate. The mask can then be removed obtain the frame lid. Next, a solder preform can be attached to the seal ring. This reduces pullback and shrinkage of the metallized layer, while lowering the manufacturing cost and process times.

[0008] Even in view of the known references, the need exists for improved lid assemblies (for providing hermetic seals) that demonstrate improvements in weight reduction and solder waste, e.g., due to solder configuration efficiencies. The need also exists for methods for making these lids.SUMMARY

[0009] The present disclosure provides a method of making a matrix comprising a plurality of lid assemblies. The method comprises mating, such as by tack welding, to a package lid material a solder preform mesh comprising solder material and defining openings to form the plurality of lid assemblies. Each lid assembly comprises a portion of package lid material and a portion of the soler preform mesh to form a solder seal ring surrounding a respective opening, and the package lid material defines a channel surrounding at least a part of the respective opening. The package lid material comprises copper, molybdenum, titanium, stainless steel foil, bronze, iron-nickel alloy, iron-nickel- cobalt alloy, a ceramic such as alumina (Al2O3), beryllia (BeO), aluminum nitride (AIN), zirconia-toughened alumina (ZTA), silicon carbide (SiC), or silicon nitride (Si3N4); an optical window such as sapphire, fused silica, borosilicate crown glass, low alkali borosilicate glass; or combinations thereof. The package lid material may be coated with an alloy coating comprising nickel alloys such as nickel-gold alloys or nickel-palladium alloys titanium alloys such as titanium-copper-nickel-gold alloys, titanium-copper-palladium- gold alloys, ortitanium-copper-palladium alloys; or chromium such as chromium-nickel- gold alloys; or combinations thereof.

[0010] The present disclosure further provides a method of making a lid assembly using a solid solder sheet. The method comprises mating, such as by tack welding, to a package lid material a solid solder preform comprising solder material. The solder preform mesh has a melting point from 150°C to 380°C and comprises indium, gold-tin alloys such as from 10 wt.% to 80 wt.% gold and from 20 wt.% to 90 wt.% tin, gold-germanium alloys, silver-tin alloys, tin-antimony alloys, tin-indium alloys, silver-indium alloys, indium-tin- silver alloys, tin-silver-copper alloys, bismuth-lead-tin alloys, indium-lead-silver alloys, indium-lead alloys, tin-lead-silver alloys, lead-tin-indium alloys, lead-tin alloys, or combinations thereof, and defines openings, which may be formed by laser cutting, to form a plurality of lid assemblies. The solder material may comprise less than 1 wt.% lead.

[0011] The package lid material comprises copper, molybdenum, titanium, stainless steel foil, bronze, iron-nickel alloy, iron-nickel-cobalt alloy, a ceramic such as alumina(Al2O3), beryllia (BeO), aluminum nitride (AIN), zirconia-toughened alumina (ZTA), silicon carbide (SiC), or silicon nitride (Si3N4); an opticalwindow such as sapphire, fused silica, borosilicate crown glass, low alkali borosilicate glass; or combinations thereof. The package lid material may be coated with an alloy coating comprising nickel alloys such as nickel-gold alloys or nickel-palladium alloys titanium alloys such as titanium-copper- nickel-gold alloys, titanium-copper-palladium-gold alloys, ortitanium-copper-palladium alloys; or chromium such as chromium-nickel-gold alloys; or combinations thereof.

[0012] The present disclosure further provides a matrix of lid assemblies, in which each lid assembly comprises a lid comprising a package lid material and a solder ring. The solder ring defines an opening, and the package lid material may comprise a channel, which may be etched, surroundingthe opening.

[0013] The present disclosure also provides a package, such as a hermetically sealed package, comprising a matrix of lid assemblies. In some cases, each lid assembly comprises a lid comprising a package lid material and a solder ring defining an opening. In some cases, each lid assembly comprises a lid comprising a package lid material and a solid solder sheet. The matrix may be mated to a package material to provide a package, such as a quad flat no-lead package, a low-temperature co-fired ceramic package, or a high-temperature co-fired ceramic package, meeting Mil-Standard 883.BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figs. 1 A and 1 B show lid assemblies with a solder stop.

[0015] Figs. 1 C and 1 D show conventional lid assemblies without a solder stop.

[0016] Fig. 2 shows a lid assembly comprising a channel and a solder preform.

[0017] Fig. 3 shows a lid assembly comprising a package lid and a solder preform.

[0018] Fig. 4 shows an exploded view of separated individual lid assemblies.

[0019] Fig. 5 shows a lid assembly comprising a solid solder preform and a package lid.DETAILED DESCRIPTIONIntroduction

[0020] As noted above, hermetically sealed packages that employ lid assemblies are known. These lid assemblies use conventional soldering materials, configurations, and techniques and sufferfrom difficulties in sealing small packages, e.g., miniature electronic packages such as semiconductor packages, due to difficulties in creating an appropriately-sized solder preform. In addition, when using these conventional production methods, solder has been found to deleteriously drip down inside the package cavity, which contaminates the contents and results in waste. Further, conventional methods yield a lid assembly that disadvantageously adds excess weight to the respective sealed packages due to requirements of greater amounts of (unnecessary) solder, which contributes to both excess weight and waste of expensive solder materials. Many, if not all, of the conventional methods do not employ a solder preform mesh. And few, if any conventional methods provide a method of making a matrix of lid assemblies.

[0021] It has now been found that, in some cases, the use of a solder preform mesh, as disclosed herein, contributes to a (matrix of) lid assemblies (versus a single discrete package, as seen conventionally) that, beneficially, make better and more efficient use of the solder. Importantly, the inventors have found that employing a solder preform mesh that defines openings in the mesh provides for considerable reductions in the weight of solder employed in the finished product (due to smaller amounts of solder), while still maintaining suitable sealing performance. In some cases, the reduction in solder mass may be up to 50% in comparison to conventional methods, providing considerable savings in both materials and expense. Further, the solder preform mesh prevents excess solder from dripping down into sealed package cavities, thereby avoiding waste and increasing the yield of hermetically sealed packages. The resultant matrix of packages further provides processing and cost-effectiveness advantages.

[0022] The present disclosure relates to a method of making a matrix comprising a plurality of lid assemblies. The method comprises the step of mating a solder preform mesh or a solid solder preform sheet to a package lid material, which may be an optical lid material, to form the plurality of lid assemblies. In cases where a solder preform mesh is employed, the solder preform mesh comprises solder material and, importantly, definesopenings in the mesh. Each lid assembly comprises a portion of the package lid material and a portion of the solder preform mesh, which forms a solder seal ring that surrounds (at least in part) the respective openings. In contrast, conventional solder preforms do not employ such openings in the preform. The conventional processes use significantly more solder than is needed to form the respective lids, leading to waste. Further, due to the (non-solder-containing) opening in the solder preform mesh, there is, advantageously, little or no solder present to drip into the package cavity, as is the case with conventional package cavities (see above). As yet another advantage, conventional methods require edge metallization, while the lid assemblies disclosed herein do not.

[0023] In some cases, the package lid may further comprise a channel around at least a portion of the openings in the solder preform mesh / lid assembly to provide a “solder stop”, e.g., the channel may define / control / limit the flow of the solder, lessening or preventing contamination of critical areas, and lessening or preventing gaps and / or voids in the solder seal. Unlike conventional solder seals which do not utilize this structure, this provides a more reliable method for creating a hermetic seal in a package, for example.

[0024] It has also been found that, by using the methods described herein, excess solder can be prevented from dripping down into sealed package cavities, even when a solid solder preform sheet is used. In some embodiments, the disclosure relates to a method of making a matrix of lid assemblies by mating a solid solder preform to a plurality of lid assemblies. By placing a package material beneath the plurality of lid assemblies prior to sealing, excess solder does not drip into the sealed package cavity. In some cases, the solid solder preform sheet is mated to a package lid material comprising a solder stop, as described above. This further ensures the lessening or prevention of excess solder dripping into the sealed package, and lessens or prevents gaps or voids in the solder seal. Further, edge metallization is not required, even when using solid solder preforms. As a result, the resultant matrix demonstrates processing and configuration benefits over conventional matrices and methods.Solder preform

[0025] As disclosed above, in some embodiments, the lid assemblies of the present disclosure comprise a particular solder preform mesh. Importantly, the solder preform defines a plurality of openings that are bordered, at least in part, by (in some cases surrounded by) solder material in the form of a solder ring seal. These openings have been found to contribute to some of the aforementioned benefits. The solder ring seal serves the purpose of hermetically sealing packages, particularly electronics packages. As discussed further below, the seal also complies with rigorous quality control guidelines.

[0026] The arrangement, size, and / or shape of the openings may vary widely. In some cases, the shape of the openings corresponds to the shape of the corresponding package. In some embodiments, the openings are arranged in lines and / or columns on a sheet. The openings may be aligned with their desired positions on the package lid material by virtue of an alignment marking.

[0027] The openings of the solder preform mesh may be formed in many suitable ways. For example, to form the openings, the solder preform may be subjected to laser cutting or mass stamping. Specifically, annular openings may be formed in the solder preform by laser cutting a plurality of inner cutout sections, each inner cutout section having an outer perimeter defined by the interior peripheral cutting edge. Some exemplary methods are described in US 11 ,049,777, which is incorporated by reference herein in its entirety.

[0028] The solder thus removed in the inner cutout sections may be reused, thereby preventing waste, as would be incurred when using a conventional solid solder preform mesh. The formation of the solder preform mesh reduces the mass of the solder by 5% to 50%, e.g., from 10% to 45%, from 15% to 40%, from 20% to 35%, or from 25% to 30%. In terms of upper limits, the solder preform mesh reduces the mass of the solder by up to 50%, e.g., up to 45%, up to 40%, up to 35%, or up to 30%. In terms of lower limits, the solder preform mesh reduces the mass of the solder by at least 5%, e.g., at least 10%, at least 15%, at least 20%, or at least 25%.

[0029] Suitable materials for the solder preform may comprise indium, gold-tin alloys, gold-germanium alloys, silver-tin alloys, tin-antimony alloys, tin-indium alloys, silverindium alloys, indium-tin-silver alloys, tin-silver-copper alloys, bismuth-lead-tin alloys,indium-lead-silver alloys, indium-lead alloys, tin-lead-silver alloys, lead-tin-indium alloys, lead-tin alloys, or combinations thereof.

[0030] In some embodiments, the solder preform may be substantially free of lead. Specifically, in some embodiments, the solder preform may comprise less than 1 wt.% lead, e.g., less than 0.5 wt.% lead, less than 0.1 wt.% lead, less than 500 ppm lead, less than 250 ppm lead, less than 100 ppm lead, less than 50 ppm lead, or less than 10 ppm lead.

[0031] The solder preform may have a melting point ranging from 150°C to 380°C, e.g., from 160°C to 370°C, from 170°C to 360°C, from 180°C to 350°C, from 190°C to 340°C, from 200°C to 330°C, from 210°C to 320°C, from 220°C to 310°C, from 230°C to 300°C, from 240°C to 290°C, from 250°C to 280°C, or from 260°C to 270°C. In terms of upper limits, the solder may have a melting point less than 380°C, e.g., less than 370°C, less than 360°C, less than 350°C, less than 340°C, less than 330°C, less than 320°C, less than 310°C, less than 300°C, less than 290°C, less than 280°C, or less than 270°C. In terms of lower limits, the solder may have a melting point greater than 150°C, e.g., greater than 160°C, greater than 170°C, greater than 180°C, greater than 190°C, greater than 200°C, greater than 210°C, greater than 220°C, greater than 230°C, greater than 240°C, greater than 250°C, or greater than 260°C.

[0032] In some embodiments, the solder preform may comprise a gold-tin alloy. The gold-tin alloy may comprise gold in an amount ranging from 10 wt.% to 80 wt.%, e.g., from 15 wt.% to 75 wt.%, form 20 wt.% to 70 wt.%, from 25 wt.% to 65 wt.%, from 30 wt.% to 60 wt.%, from 35 wt.% to 55 wt.%, or from 40 wt.% to 50 wt.%. In terms of upper limits, the gold-tin alloy may comprise gold in an amount less than 80 wt.%, e.g., less than 75 wt.%, less than 70 wt.%, less than 65 wt.%, less than 60 wt.%, less than 55 wt.%, less than 50 wt.%, or less than 45 wt.%. In terms of lower limits, the gold-tin alloy may comprise gold in an amount greater than 10 wt.%, e.g., greater than 15 wt.%, greater than 20 wt.%, greater than 25 wt.%, greater than 30 wt.%, greater than 35 wt.%, or greater than 40 wt.%.

[0033] The gold-tin alloy may comprise tin in an amount ranging from 20 wt.% to 90 wt.%, e.g., from 25 wt.% to 85 wt.%, from 30 wt.% to 80 wt.%, from 35 wt.% to 75 wt.%,from 40 wt.% to 70 wt.%, from 45 wt.% to 65 wt.%, or from 50 wt.% to 60 wt.%. In terms of upper limits, the gold-tin alloy may comprise tin in an amount less than 90 wt.%, e.g., less than 85 wt.%, less than 80 wt.%, less than 75 wt.%, less than 70 wt.%, less than 65 wt.%, less than 60 wt.%, or less than 55 wt.%. In terms of lower limits, the gold-tin alloy may comprise tin in an amount greater than 20 wt.%, e.g., greater than 25 wt.%, greater than 30 wt.%, greater than 35 wt.%, greater than 40 wt.%, greater than 45 wt.%, or greater than 50 wt.%.

[0034] In some embodiments, the gold-tin alloy may comprise 80 wt.% gold and 20 wt.% tin. In some embodiments, the gold-tin alloy may comprise 78 wt.% gold and 22 wt.% tin. In some embodiments, the gold-tin alloy may comprise 10 wt.% gold and 90 wt.% tin.

[0035] The solder may comprise impurities in very low amounts, e.g., less than 200 ppm, less than 150 ppm, less than 100 ppm, less than 75 ppm, less than 50 ppm, less than 25 ppm, or less than 10 ppm.

[0036] Advantageously, the solder preform mesh may allow for a narrower solder ring than those achievable using conventional methods. For example, in some embodiments, the width of the solder ring may range from 0.1 mm to 10 mm, e.g., from 0.2 mm to 9.5 mm, from 0.3 mm to 9.0 mm, from 0.4 mm to 8.5 mm, from 0.5 mm to 8.0 mm, from 0.6 mm to 7.5 mm, from 0.7 mm to 7.0 mm, from 0.8 mm to 6.5 mm, from 0.9 mm to 6.0 mm, from 1 .0 mm to 5.5 mm, from 1 .5 mm to 5.0 mm, from 2.0 mm to 4.5 mm, from 2.5 mm to 4.0 mm, or from 3.0 mm to 3.5 mm. In terms of upper limits, the width of the solder ring may be less than 10 mm, e.g., less than 9.5 mm, less than 9.0 mm, less than 8.5 mm, less than 8.0 mm, less than 7.5 mm, less than 7.0 mm, less than 6.5 mm, less than 6.0 mm, less than 5.5 mm, less than 5.0 mm, less than 4.5 mm, less than 4.0 mm, or less than 3.5 mm. In terms of lower limits, the width of the solder ring may be greater than 0.1 mm, e.g., greater than 0.2 mm, greater than 0.3 mm, greater than 0.4 mm, greater than 0.5 mm, greaterthan 0.6 mm, greaterthan 0.7 mm, greater than 0.8 mm, greater than 0.9 mm, greaterthan 1 .0 mm, greaterthan 1 .5 mm, greater than 2.0 mm, greaterthan 2.5 mm, or greater than 3.0 mm.

[0037] The tolerance for the length and / or width of the solder preform mesh may be less than + 0.15 mm, e.g., less than + 0.14 mm, less than + 0.13 mm, less than + 0.12 mm,less than + 0.11 mm, less than + 0.10 mm, less than + 0.09 mm, less than + 0.08 mm, less than + 0.07 mm, less than + 0.06 mm, or less than + 0.05 mm.

[0038] The thickness of the solder preform mesh may range from 0.01 mm to 10 mm, e.g., 0.02 mm to 10 mm, 0.1 mm to 10 mm, from 0.2 mm to 9.5 mm, from 0.3 mm to 9.0 mm, from 0.4 mm to 8.5 mm, from 0.5 mm to 8.0 mm, from 0.6 mm to 7.5 mm, from 0.7 mm to 7.0 mm, from 0.8 mm to 6.5 mm, from 0.9 mm to 6.0 mm, from 1 .0 mm to 5.5 mm, from 1 .5 mm to 5.0 mm, from 2.0 mm to 4.5 mm, from 2.5 mm to 4.0 mm, or from 3.0 mm to 3.5 mm. In terms of upper limits, the thickness of the solder ring may be less than 10 mm, e.g., less than 9.5 mm, less than 9.0 mm, less than 8.5 mm, less than 8.0 mm, less than 7.5 mm, less than 7.0 mm, less than 6.5 mm, less than 6.0 mm, less than 5.5 mm, less than 5.0 mm, less than 4.5 mm, less than 4.0 mm, or less than 3.5 mm. In terms of lower limits, the thickness of the solder ring may be greater than 0.01 mm, e.g., greater than 0.1 mm, greaterthan 0.2 mm, greater than 0.3 mm, greater than 0.4 mm, greaterthan 0.5 mm, greater than 0.6 mm, greater than 0.7 mm, greater than 0.8 mm, greaterthan 0.9 mm, greaterthan 1 .0 mm, greater than 1 .5 mm, greater than 2.0 mm, greaterthan 2.5 mm, orgreater than 3.0 mm.

[0039] The tolerance for the thickness of the solder preform mesh may be less than + 0.015 mm, e.g., less than ± 0.014 mm, less than ± 0.013 mm, less than ± 0.012 mm, less than + 0.011 mm, less than + 0.010 mm, less than + 0.009 mm, less than + 0.008 mm, less than ± 0.007 mm, less than ± 0.006 mm, or less than ± 0.005 mm.

[0040] In some embodiments, a solid solder sheet is employed to produce the matrix. In such cases, the composition and characteristics of the solder sheet may be similarto or the same as the parameters described above. Stated another way, the solder in the solid solder preform used in such methods may be the same or similarto solder of the solder preform mesh. The solid solder preform used in some of the processes described herein provides the benefit of ease of manufacture while advantageously avoiding conventional problems of solder leakage and beneficially permitting the manufacture of a matrix of lid assemblies instead of a single discrete package.Solder Stop

[0041] As disclosed above, the package lid may further comprise a channel around at least a portion of the openings in the solder preform mesh / lid assembly to provide a solder stop. The solder stop advantageously prevents the solder flow from dripping into a package and contaminating its contents. The solder stop further provides a more seamless seal, lessening or preventing voids or gaps in the solder seal, providing hermetically sealed packages. In contrast, in conventional methods without a solder stop, solder overflow may lead to contamination of package contents and incomplete sealingwith gaps and / or voids in the solder seal. Importantly, the methods disclosed herein do not rely on adhesives and / or epoxies to form a seal. This is beneficial because epoxy and other adhesives may be expensive and contribute to processing complexity. Further, the methods disclosed herein provide for a rigid lid assembly / package, as opposed to conventional methods that rely on films.

[0042] The channeled (solder stop) configuration beneficially contributes to the prevention of solder from dripping into the package during sealing, providing a protective package for sensitive components, such as electronics, without reliance on conventional adhesives.

[0043] Referring to Fig. 2, because of the solder stop, the solder 210 does not extend over the portion of the lid 220 to be enclosed within the package. Importantly, this prevents the contents of the package from contamination with undesired solder and also prevents waste by avoiding damage of components, loss of hermetic seals, and overuse of solder, as in conventional methods.

[0044] If desired, the solid solder preforms may be mated to a package lid material comprising a solder stop, as described above. Thus, unlike conventional methods, even when the solid solder preforms are used, the solder flow may be defined, controlled or limited as it melts.

[0045] As shown in Figs. 1 A and 1 B, the employment of solder stop 110 reduces or prevents undesirable spreading of solder during heating and / or sealing. In contrast, in conventional methods without the solder stop, solder may spread undesirably. As shown in Figs. 1 C and 1 D, solder spread may lead to contamination of critical regions, such aspackage contents. Additionally, the lack of control over solder flow in conventional methods leads to gaps and / orvoids in the seal, leadingto leaks and preventing a truly hermetic seal. Importantly, the solder stop described herein controls the solder flow, thereby improving the quality of the seal, and lessening or preventing solder overflow.

[0046] The channel may be formed by etching, for example. Etched package lids, such as those comprising a solder stop, may further comprise a tie bar, which functions to provide structure to the lid assembly to anchor the solder and provide hermetic seals.

[0047] The solder stop and / or tie bar may be particularly suitable for use in small packages, e.g., miniature electronics packages. Manufacture of these products is often challenging due to the aforementioned difficulties in controlling solder flow. Thus, the package lids of the present disclosure may offer significant improvements in packaging and efficiency.Package lid material

[0048] The configuration and composition of the package lid material may vary widely. In some cases, the package lid material may be a flat package lid material. In some cases, the package lid and the material from which it is made may serve the purpose of providing structure to the lid assembly to anchor the solder. This, in turn, permits hermetic seals. The package lid material may provide desirable CTE (coefficient of thermal expansion), particularly after the package is formed as discussed further below.

[0049] In some embodiments, the package lid material comprises metal or a metal alloy. Suitable metals and metal alloys may comprise copper, titanium, stainless steel foil, molybdenum, bronze, iron-nickel alloy, or iron-nickel-cobalt alloy, or combinations thereof.

[0050] In some cases, the package lid comprises a ceramic material. Suitable ceramics may comprise alumina (Al2O3), beryllia (BeO), aluminum nitride (AIN), zirconia- toughened alumina (ZTA), silicon carbide (SiC), silicon nitride (Si3N4), or combinations thereof.

[0051] In some cases, the package lid comprises an optical substrate (window).Suitable optical windows may comprise sapphire, fused silica, borosilicate windows suchas borosilicate crown glass and low alkali borosilicate glass, or combinations thereof. Suitable commercially available materials may include N-BK7 and D263T, for example.

[0052] Optical windows may be coated with an anti-reflective coating. If desired, the anti-reflective coating may be applied to both sides of the optical window. Suitable anti- reflective coatings may comprise zirconium oxide, titanium dioxide, silicon dioxide, silicon monoxide, and magnesium fluoride, among others.

[0053] In some embodiments, the package lid may be metalized. In otherwords, the may be coated with a metal coating. Suitable coatings may comprise metals and metal alloys, such as gold, nickel alloys, titanium alloys, or chromium alloys, or combinations thereof, for example. More specifically, suitable alloys may comprise nickel-gold alloys, nickel-palladium alloys, titanium-copper alloys, titanium-copper-nickel-gold alloys, titanium-copper-palladium-gold alloys, titanium-copper-palladium alloys, or chromium- nickel-gold alloys, or combinations thereof.

[0054] In some cases, the coating may be substantially free of iron. In such cases, the coating may be particularly suitable for medical and space applications.

[0055] The package lid may be masked prior to metallization. Masking may be performed via polyamide masking or by using a photo-litho process, for example.

[0056] The metal coating may be deposited on the package lid by wet plating or evaporation, for example. Suitable materials for wet plating may include nickel-gold alloys and nickel-palladium alloys. Alternatively, the metal coating may be deposited on the package lid by physical vapor deposition (PVD) in combination with wet plating. As a further alternative, the metal coating may be deposited by electroplating. Suitable materials for this process may comprise titanium-copper-nickel-gold alloys, titaniumcopper-palladium-gold alloys, titanium-copper-palladium alloys, and chromium-nickel- gold alloys, for example.

[0057] The thickness of the coating may range from 1 pm to 50 pm, e.g., from 5 pm to 45 pm, from 10 pm to 40 pm, from 15 pm to 35 pm, or from 20 pm to 30 pm. In terms of upper limits, the thickness of the coating may be less than 50 pm, e.g., less than 45 pm, less than 40 pm, less than 35 pm, less than 30 pm, or less than 25 pm. In terms of lowerlimits, the thickness of the coating may be greater than 1 pm, e.g., greater than 5 pm, greaterthan 10 pm, greaterthan 15 pm, or greaterthan 20 pm.

[0058] In some cases, the coating may comprise more than one layer. For example, the coating may comprise a first layer comprising a first metal or metal alloy and a second layer comprising a second metal or metal alloy. If desired, further layers, e.g., a third layer comprising a third metal or metal alloy, etc., may be added.

[0059] In such cases, the thickness of the first layer may range from 0.001 pm to 9.0 pm, e.g., from 0.005 pm to 8.75 pm , from 0.01 pm to 8.5 pm, from 0.5 pm to 8.0 pm , from 0.1 pm to 7.5 pm , from 0.5 pm to 7.0 pm, from 1 .0 pm to 6.5 pm, from 1.5 pm to 6.0 pm, from 2.0 pm to 5.5 pm, from 2.5 pm to 5.0 pm, from 3.0 pm to 4.5 pm, or from 3.5 pm to 4.0 pm. In terms of upper limits, the thickness of the first layer may be less than 9.0 pm, e.g., less than 8.75 pm , less than 8.5 pm , less than 8.0 pm , less than 7.5 pm, less than 7.0 pm, less than 6.5 pm, less than 6 .0 pm, less than 5.5 pm, less than 5.0 pm, less than 4.5 pm, or less than 4.0 pm. In terms of lower limits, the thickness of the first layer may be greater than 0.001 pm, greater than 0.005 pm, greater than 0.01 pm, greater than 0.05 pm, greater than 0.1 pm, greaterthan 0.5 pm, greaterthan 1 .0 pm, greater than 1.5 pm, greater than 2.0 pm, greaterthan 2.5 pm, greaterthan 3.0 pm, or greater than 3.5 pm.

[0060] The second layer may range from 0.001 pm to 1 .5 pm, e.g., 0.001 pm to 1 .25 pm, from 0.005 pm to 1 .0 pm, from 0.01 pm to 0.9 pm, from 0.02 pm to 0.8 pm, from 0.03 pm to 0.7 pm, from 0.04 pm to 0.6 pm, from 0.05 pm to 0.5 pm, from 0.06 pm to 0.4 pm, from 0.07 pm to 0.3 pm, from 0.08 pm to 0.2 pm, or from 0.09 pm to 0.1 pm. In terms of upper limits, the thickness of the second layer may be less than 1 .5 pm, e.g., less than 1 .25 pm, less than 1 pm, less than 0.9 pm, less than 0.8 pm, less than 0.7 pm, less than 0.6 pm, less than 0.5 pm, less than 0.4 pm, less than 0.3 pm, less than 0.2 pm, less than 0.1 pm, or less than 0.09 pm. In terms of lower limits, the thickness of the second layer may be greater than 0.001 pm, greater than 0.002 pm, greater than 0.003 pm, greater than 0.004 pm, greater than 0.005 pm, greater than 0.006 pm, greater than 0.007 pm, greater than 0.008 pm, greater than 0.009 pm, greater than 0.01 pm, greater than 0.02 pm, greater than 0.03pm, greater than 0.04 pm, greater than 0.05 pm, greater than 0.06 pm, greater than 0.07 pm, or greater than 0.08 pm.

[0061] The thickness of the third layer, if present, may range from 0.001 pm to 9.0 pm, e.g., from 0.005 pm to 8.75 pm , from 0.01 pm to 8.5 pm, from 0.5 pm to 8.0 pm , from 0.1 pm to 7.5 pm , from 0.5 pm to 7.0 pm, from 1 .0 pm to 6.5 pm, from 1.5 pm to 6.0 pm, from 2.0 pm to 5.5 pm, from 2.5 pm to 5.0 pm, from 3.0 pm to 4.5 pm, or from 3.5 pm to 4.0 pm. In terms of upper limits, the thickness of the first layer may be less than 9.0 pm, e.g., less than 8.75 pm , less than 8.5 pm , less than 8.0 pm , less than 7.5 pm, less than 7.0 pm, less than 6.5 pm, less than 6 .0 pm, less than 5.5 pm, less than 5.0 pm, less than 4.5 pm, or less than 4.0 pm. In terms of lower limits, the thickness of the first layer may be greater than 0.001 pm, greater than 0.005 pm, greater than 0.01 pm, greater than 0.05 pm, greater than 0.1 pm, greater than 0.5 pm, greater than 1 .0 pm, greater than 1.5 pm, greater than 2.0 pm, greater than 2.5 pm, greater than 3.0 pm, or greater than 3.5 pm.

[0062] Further layers, if present, may be of similar thickness to the first, second, and / or third layers as described above.

[0063] The total thickness of all layers may range from 0.002 pm to 12.0 pm, e.g., from 0.005 pm to 11 .75 pm, from 0.01 pm to 11 .50 pm, from 0.05 pm to 11 .25 pm, from 0.1 pm to 11 .0 pm, from 0.5 pm to 10.5 pm, from 1 .0 pm to 10.0 pm, from 2.0 pm to 9.0 pm, from 3.0 pm to 8.0 pm, from 4.0 pm to 7.0 pm, or from 5.0 pm to 6.0 pm. In terms of upper limits, the total thickness of all layers may be less than 12.0 pm, e.g., less than 11 .75 pm, less than 11 .5 pm, less than 11.25 pm, less than 11 .0 pm, less than 10.5 pm, less than 10.0 pm, less than 9.0 pm, less than 8.0 pm, less than 7.0 pm, or less than 6.0 pm. In terms of lower limits, the total thickness of all layers may be greater than 0.002 pm, e.g., greaterthan 0.005 pm, greater than 0.01 pm, greater than 0.05 pm, greater than 0.1 pm, greater than 0.5 pm, greater than 1.0 pm, greater than 2.0 pm, greater than 3.0 pm, greater than 4.0 pm, or greater than 5.0 pm,

[0064] In some embodiments, the first layer may comprise titanium or chromium. In some embodiments, the second layer may comprise copper or nickel. In someembodiments, the third layer may comprise gold. In some cases, the coating may comprise alternating layers, e.g., nickel-gold-nickel-gold.

[0065] As disclosed above, conventional methods require edge metallization when ceramic lids are used. However, the lid assemblies disclosed herein do not require edge metallization, even when ceramic flat lids are used. This allows for separation of discrete components (individual lids) from the matrix assembly. Separation may comprise dicing, cutting, or cleaving, for example. If desired, separation may be performed once the package has been formed, as discussed further below.

[0066] The thickness of the lid may range from 0.01 cm to 5.0 cm, e.g., from 0.1 cm to 5.0 cm, from 0.5 cm to 4.5 cm, from 1 cm to 4.0 cm, from 1.5 cm to 3.5 cm, or from 2.0 cm to 3.0 cm. In terms of upper limits, the thickness of the lid may be less than 5.0 cm, e.g., less than 4.5 cm, less than 4.0 cm, less than 3.5 cm, or less than 3.0 cm. In terms of lower limits, the thickness of the lid may be greater than 0.01 cm, e.g., greaterthan 0.1 cm, greater than 0.5 cm, greaterthan 1 .0 cm, greater than 1.5 cm, greater than 2.0 cm, or greaterthan 2.5 cm. In some embodiments, the thickness of the lid may range from 0.01 cm to 0.1 cm. In some embodiments, the lid may be thickerthan the solder layer.

[0067] The thickness dimension tolerance may be less than + 0.008 cm, e.g., less than ± 0.0075 cm, less than ± 0.0070 cm, less than ± 0.0065 cm, less than + 0.0060 cm, less than + 0.0055 cm, less than + 0.0050 cm, less than + 0.0045 cm, less than + 0.0040 cm, less than ± 0.0035 cm, less than ± 0.0030 cm, less than ± 0.0025 cm, less than ± 0.0020 cm, less than ±0.0015, or less than + 0.0010 cm.

[0068] The solder preform mesh or the solid solder preform may be mated to the package lid material by means of tack welding, reflow, or brazing, for example.

[0069] As disclosed above, the solder preform mesh-package lid material combination define openings, e.g., the openings in the preform mesh, when mated, become openings in the lid assembly. In some embodiments, the package lid may further comprise a channel, or solder stop, around at least a portion of the openings in the solder preform mesh / lid assembly.

[0070] When a solid solder sheet is desired, solder overflow may be lessened or prevented by sealing the package in an upside down position; e.g., by placing the package material atop the matrix of lid assemblies followed by mating the package to the matrix. This position allows the solder to spread without dripping into the package, thereby limiting or preventing damage of the components in the package.

[0071] The solid solder sheet may therefore also be suited to the manufacture of small packages, such as miniature electronics packages, while continuingto offer improvements over conventional methods for packaging and efficiency.Packages

[0072] As disclosed above, the completed lid assembly may be particularly suitable for hermetically sealed packages, such as semiconductor packages and miniature electronic packages, for example. Specifically, the matrix of lid assemblies may be mated to a package material to provide the package. When the package lid comprises a ceramic, the completed lid assembly may be particularly suitable for use in low temperature co-fired ceramic (LTCC) packaging and / or high temperature co-fired ceramic (HTCC) packaging. When the solder material is substantially free of lead, the completed lid assembly may be particularly suitable for quad flat no-lead (QFN) packages.

[0073] As an alternative to separating the lid assembly into individual lid assemblies as discussed above, separation may be performed after the matrix of lid assemblies is mated to the package material to provide a matrix of packages. The matrix of packages may be separated to provide individual packages as delineated by the openings in the solder preform mesh and / or solder stop.

[0074] When a solid solder preform is used, the matrix of lid assemblies may be mated to the package material to provide a matrix of sealed packages, which may then be separated to provide individual packages according to the desired size or as delineated by the solder stop. In some cases, it may be preferable to use a package lid material without edge metallization as such metallization may be damaged during the separation process. The package may meet rigorous quality standards, as described in Mil-Standard 883 which provides methods to determine whether microelectronics devices are suitable for use inmilitary and / or aerospace electronics systems. Specifically, the packages disclosed herein meet the standards of Mil-Standard 883 for fine leak, gross leak, salt spray or SAT testing, thermal cycle testing, centrifuge testing, and X-ray testing.ExamplesExample 1 and Comparative Example A

[0075] Example 1 was prepared by tack welding a solder preform comprising an opening to a package lid material to provide a lid assembly. The package lid material defined a channel around the opening, which acts as a solder stop (see Figs. 1A and 1 B). The lid assembly of Comparative Example A did not employ such a solder stop (see Figs 1 C and 1 D). The lid assemblies were heated to simulate sealing and package formation. As can be seen in Figs. 1A and 1 B, during and after the heating, no solder overflow was noted in Example 1 , while Figs. 1 C and 1 D show that Comparative Example A demonstrated significant deleterious overflow 130 (Fig. 1 C), as well as contamination from solder creep 140 and 150 (Fig. 1 D).Example 2

[0076] A matrix of lid assemblies as shown as shown in Figs. 2 and 3 was prepared by tack welding a package lid material 310 to a solder preform mesh 320. As shown in Fig. 4, once the lid assemblies 410 were formed, they were separated to form individual (discrete) lid assemblies, shown in an exploded view 420.

[0077] Next, as shown in Fig. 5, a solid solder preform 520 was mated to a package lid material 530 via tack welding to provide a lid assembly 510. Once the lid assemblies were formed, they were separated to form individual lid assemblies.

[0078] Beneficially, in addition to the advantages noted above, Examples 1 and 2 each provide a matrix of packages, not a single discrete package, which has the accompanying advantages and benefits discussed herein.

[0079] As used herein, “greater than” and “less than” limits may also include the number associated therewith. Stated another way, “greater than” and “less than” may be interpreted as “greater than or equal to” and “less than or equal to.” It is contemplated that this language may be subsequently modified in the claims to include “or equal to.” Forexample, “greater than 4.0” may be interpreted as, and subsequently modified in the claims as “greater than or equal to 4.0.”

[0080] In some embodiments, any or some of the components or steps disclosed herein may be considered optional. In some cases, the disclosed compositions may expressly exclude any or some of the aforementioned components or steps in this description, e.g., via claim language. For example, claim language may be modified to recite that the powder mixture does not utilize or comprise a component, e.g., the lid assembly does not comprise a tie bar. Such negative limitations are contemplated, and this text serves as support for negative limitations for components, steps, and / or features. Embodiments

[0081] As used below, any reference to a series of embodiments is to be understood as a reference to each of those embodiments disjunctively (e.g., “Embodiments 1 - 4” is to be understood as “Embodiments 1 , 2, 3, or 4”).

[0082] Embodiment 1 : A method of making a matrix comprising a plurality of lid assemblies, the method comprising: mating to a package lid material a solder preform mesh comprising solder material and defining openings to form the plurality of lid assemblies; wherein each lid assembly comprises a portion of the package lid material and a portion of the solder preform mesh to form a solder seal ring surrounding a respective opening; and wherein the package lid material defines a channel surrounding at least a part of the respective opening.

[0083] Embodiment 2: The method of Embodiment 1 , wherein the package lid material comprises copper, molybdenum, titanium, stainless steel foil, bronze, iron-nickel alloy, iron-nickel-cobalt alloy, ceramic, an optical window, or combinations thereof.

[0084] Embodiment 3: The method of Embodiment 1 or Embodiment 2, wherein the ceramic comprises alumina (Al2O3), beryllia (BeO), aluminum nitride (AIN), zirconia- toughened alumina (ZTA), silicon carbide (SiC), or silicon nitride (Si3N4), or combinations thereof.

[0085] Embodiment 4: The method of Embodiment 1 or Embodiment 2, wherein the optical window comprises sapphire, fused silica, borosilicate crown glass, low alkali borosilicate glass, or combinations thereof.

[0086] Embodiment 5: The method of Embodiment 1 or Embodiment 2, wherein the package lid material comprises an alloy coating comprising nickel alloys, titanium alloys, or chromium alloys, or combinations thereof.

[0087] Embodiment 6: The method of Embodiment 5, wherein the package lid material comprises an alloy coating comprising nickel-gold alloys, nickel-palladium alloys, titanium-copper-nickel-gold alloys, titanium-copper-palladium-gold alloys, titanium- copper-palladium alloys, or chromium-nickel-gold alloys, or combinations thereof.

[0088] Embodiment 7: The method of any of Embodiments 1-6, wherein the solder preform comprises indium, gold-tin alloys, gold-germanium alloys, silver-tin alloys, tinantimony alloys, tin-indium alloys, silver-indium alloys, indium-tin-silver alloys, tin-silver- copper alloys, bismuth-lead-tin alloys, indium-lead-silver alloys, indium-lead alloys, tin- lead-silver alloys, lead-tin-indium alloys, lead-tin alloys, or combinations thereof.

[0089] Embodiment 8: The method of Embodiment 7, wherein the solder preform comprises gold-tin alloys, gold-germanium alloys, tin-antimony alloys, tin-indium alloys, silver-indium alloys, or tin-silver-copper alloys, or combinations thereof.

[0090] Embodiment 9: The method of Embodiment 8, wherein the solder material comprises less than 1 wt.% lead.

[0091] Embodiment 10: The method of any of Embodiments 7-9, wherein the solder preform comprises from 10 wt.% to 80 wt.% gold and from 20 wt.% to 90 wt.% tin.

[0092] Embodiment 11 : The method of any of Embodiments 1 -10, wherein the solder preform has a melting point from 150°C to 380°C.

[0093] Embodiment 12: The method of any of Embodiments 1 -11 , wherein the mating comprises tack welding.

[0094] Embodiment 13: The method of any of Embodiments 1 -12, wherein the openings in the solder preform mesh are formed by laser cutting.

[0095] Embodiment 14: A matrix of lid assemblies, each lid assembly comprising: a lid comprising a package lid material; and a solder ring defining an opening; wherein the package lid material defines a channel surrounding at least a part of the respective opening.

[0096] Embodiment 15: The matrix of Embodiment 14, wherein the channel is formed by etching.

[0097] Embodiment 16: A package comprising: a matrix of lid assemblies, each lid assembly comprising: a lid comprising a package lid material; and a solder ring defining an opening; wherein the package lid material comprises a channel surrounding the opening; and wherein the matrix is mated to a package material to provide a package that meets Mil- Standard 883.

[0098] Embodiment 17: The package of Embodiment 16, wherein the package comprises a quad flat no-lead package, a low-temperature co-fired ceramic package, or a high-temperature co-fired ceramic package.

[0099] Embodiment 18: The package of either Embodiment 16 or Embodiment 17, wherein the package comprises a hermetic seal that withstands a gross leak to fine leak rate level as measured by Mil-Std 883.

[0100] Embodiment 19: A method of making a matrix comprising a plurality of lid assemblies, the method comprising: mating to a package lid material a solid solder preform comprising solder material to form the plurality of lid assemblies; wherein each lid assembly comprises a portion of package lid material and a portion of the solid solder preform; wherein the solder preform comprises indium, gold-tin alloys, gold-germanium alloys, silver-tin alloys, tin-antimony alloys, tin-indium alloys, silver-indium alloys, indiumtin-silver alloys, tin-silver-copper alloys, bismuth-lead-tin alloys, indium-lead-silver alloys, indium-lead alloys, tin-lead-silver alloys, lead-tin-indium alloys, lead-tin alloys, or combinations thereof; and wherein the solder preform has a melting point from 150°C to 380°C.

[0101] Embodiment 20: The method of Embodiment 19, wherein the package lid material defines a channel surrounding at least a part of the solid solder preform.

[0102] Embodiment 21 : The method of Embodiment 19 or Embodiment 20, wherein the package lid material comprises copper, molybdenum, titanium, stainless steel foil, bronze, iron-nickel alloy, iron-nickel-cobalt alloy, ceramic, an optical window, or combinations thereof.

[0103] Embodiment 22: The method of Embodiment 21 , wherein the ceramic comprises alumina (Al2O3), beryllia (BeO), aluminum nitride (AIN), zirconia-toughened alumina (ZTA), silicon carbide (SiC), or silicon nitride (Si3N4), or combinations thereof.

[0104] Embodiment 23: The method of Embodiment 21 , wherein the optical window comprises sapphire, fused silica, borosilicate crown glass, low alkali borosilicate glass, or combinations thereof.

[0105] Embodiment 24: The method of Embodiment 21, wherein the package lid material comprises an alloy coating comprising nickel alloys, titanium alloys, or chromium alloys, or combinations thereof.

[0106] Embodiment 25: The method of Embodiment 24, wherein the package lid material comprises an alloy coating comprising nickel-gold alloys, nickel-palladium alloys, titanium-copper-nickel-gold alloys, titanium-copper-palladium-gold alloys, titanium- copper-palladium alloys, or chromium-nickel-gold alloys, or combinations thereof.

[0107] Embodiment 26: The method of any of Embodiments 19-25, wherein the solder preform comprises gold-tin alloys, gold-germanium alloys, tin-antimony alloys, tin-indium alloys, silver-indium alloys, or tin-silver-copper alloys, or combinations thereof.

[0108] Embodiment 27: The method of Embodiment 26, wherein the solder material comprises less than 1 wt.% lead.

[0109] Embodiment 28: The method of any of Embodiments 19-27, wherein the solder preform comprises from 10 wt.% to 80 wt.% gold and from 20 wt.% to 90 wt.% tin.

[0110] Embodiment 29: The method of any of Embodiments 19-28, wherein the mating comprises tack welding.

[0111] Embodiment 30: A matrix of lid assemblies, each lid assembly comprising: a lid comprising a package lid material; and a solid solder preform.

Claims

We Claim:1 . A method of making a matrix comprising a plurality of lid assemblies, the method comprising: mating to a package lid material a solder preform mesh comprising solder material and defining openings to form the plurality of lid assemblies; wherein each lid assembly comprises a portion of the package lid material and a portion of the solder preform mesh to form a solder seal ring surrounding a respective opening; and wherein the package lid material defines a channel surrounding at least a part of the respective opening.

2. The method of claim 1 , wherein the package lid material comprises copper, molybdenum, titanium, stainless steel foil, bronze, iron-nickel alloy, iron-nickel-cobalt alloy, ceramic, an optical window, or combinations thereof.

3. The method of claim 2, wherein the ceramic comprises alumina (Al2O3), beryllia (BeO), aluminum nitride (AIN), zirconia-toughened alumina (ZTA), silicon carbide (SiC), or silicon nitride (Si3N4), or combinations thereof.

4. The method of claim 2, wherein the optical window comprises sapphire, fused silica, borosilicate crown glass, low alkali borosilicate glass, or combinations thereof.

5. The method of claim 2, wherein the package lid material comprises an alloy coating comprising nickel alloys, titanium alloys, or chromium alloys, or combinations thereof.

6. The method of claim 5, wherein the package lid material comprises an alloy coating comprising nickel-gold alloys, nickel-palladium alloys, titanium-copper-nickel-gold alloys, titanium-copper-palladium-gold alloys, titanium-copper-palladium alloys, or chromium- nickel-gold alloys, or combinations thereof.

7. The method of claim 1 , wherein the solder preform comprises indium, gold-tin alloys, gold-germanium alloys, silver-tin alloys, tin-antimony alloys, tin-indium alloys, silver-indium alloys, indium-tin-silver alloys, tin-silver-copper alloys, bismuth-lead-tin alloys, indium-lead-silver alloys, indium-lead alloys, tin-lead-silver alloys, lead-tin-indium alloys, lead-tin alloys, or combinations thereof.

8. The method of claim 7, wherein the solder preform comprises gold-tin alloys, goldgermanium alloys, tin-antimony alloys, tin-indium alloys, silver-indium alloys, or tin-silver- copper alloys, or combinations thereof.

9. The method of claim 8, wherein the solder material comprises less than 1 wt.% lead.

10. The method of claim 7, wherein the solder preform comprises from 10 wt.% to 80 wt.% gold and from 20 wt.% to 90 wt.% tin.11 . The method of claim 1 , wherein the solder preform has a melting point from 150°C to 380°C.

12. The method of claim 1 , wherein the mating comprises tack welding.

13. The method of claim 1 , wherein the openings in the solder preform mesh are formed by laser cutting.

14. A matrix of lid assemblies, each lid assembly comprising: a lid comprising a package lid material; and a solder ring defining an opening; wherein the package lid material comprises a channel surrounding at least a part of the opening.

15. The matrix of claim 14, wherein the channel is formed by etching.

16. A package comprising: a matrix of lid assemblies, each lid assembly comprising: a lid comprising a package lid material; and a solder ring defining an opening; wherein the package lid material comprises a channel surroundingthe opening; and wherein the matrix is mated to a package material to provide a package that meets Mil-Standard 883.

17. The package of claim 16, wherein the package comprises a quad flat no-lead package, a low-temperature co-fired ceramic package, or a high-temperature co-fired ceramic package.

18. The package of claim 16, wherein the package comprises a hermetic seal that withstands a gross leak to fine leak rate level as measured by Mil-Std 883.

19. A method of making a matrix comprising a plurality of lid assemblies, the method comprising: mating to a package lid material a solid solder preform comprising solder material to form the plurality of lid assemblies; wherein each lid assembly comprises a portion of the package lid material and a portion of the solid solder preform; wherein the solder preform comprises indium, gold-tin alloys, gold-germanium alloys, silver-tin alloys, tin-antimony alloys, tin-indium alloys, silver-indium alloys, indium- tin-silver alloys, tin-silver-copper alloys, bismuth-lead-tin alloys, indium-lead-silver alloys, indium-lead alloys, tin-lead-silver alloys, lead-tin-indium alloys, lead-tin alloys, or combinations thereof; and wherein the solder preform has a melting point from 150°C to 380°C.

20. The method of claim 19, wherein the package lid material defines a channel surrounding at least a part of the solid solder preform.

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