Hermetically sealed glass package including a heat-dissipating base substrate, a cap, and a laser bonding line
A hermetically sealed package includes: a heat-dissipating base substrate configured for dissipating heat from the hermetically sealed package; a cap arranged on the heat-dissipating base substrate, the cap and the heat-dissipating base substrate jointly forming at least a part of the package; at least one functional area hermetically sealed by the package; at least one laser bonding line configured for hermetically sealing the package, the laser bonding line having a height perpendicular to a bonding plane of the laser bonding line.
1 . A hermetically sealed package, comprising:
a heat-dissipating base substrate configured for dissipating heat from the hermetically sealed package;
a cap arranged on the heat-dissipating base substrate, the cap and the heat-dissipating base substrate jointly forming at least a part of the package, the cap at least partially defining at least one functional area hermetically sealed by the package; and
at least one laser bonding line configured for hermetically sealing the package, the at least one laser bonding line being associated with at least one of the cap and the heat-dissipating base substrate and having a height perpendicular to a bonding plane of the at least one laser bonding line, the heat-dissipating base substrate comprising a metallic nitride which is an aluminum nitride ceramic, the heat-dissipating base substrate being directly joined to the cap or to an intermediate substrate, the at least one laser bonding line extending into a material of the cap over the height and, on an opposite side of the at least one laser bonding line, extending into a material of the heat-dissipating base substrate or a material of the intermediate substrate, the at least one laser bonding line forming a hermetic seal, and the at least one laser bonding line circumferentially surrounding the at least one functional area at a distance therefrom.
2 . The hermetically sealed package of claim 1 , wherein at least one of:
the heat-dissipating base substrate is made of the material having a high thermal conductivity; and
thermal conductivity of the heat-dissipating base substrate is one of at least 100 W/(m*K), at least 150 W/(m*K), and at least 170 W/(m*K).
3 . The hermetically sealed package of claim 1 , wherein the cap comprises a vitreous material, which is one of a glass, a glass ceramic, a silicon, a sapphire, and a combination thereof.
4 . The hermetically sealed package of claim 1 , wherein at least one of:
the cap is joined to the heat-dissipating base substrate by the at least one laser bonding line; and
the cap and the heat-dissipating base substrate jointly and completely form the hermetically sealed package.
5 . The hermetically sealed package of claim 1 , wherein the hermetically sealed package is configured for accommodating at least one accommodation item which is one of an electronic circuit, an electronic circuit device, a sensor, and a micro-electromechanical system, wherein at least one of:
the at least one functional area is adapted to accommodate the at least one accommodation item; and
the at least one accommodation item is arranged on the heat-dissipating base substrate and inside the hermetically sealed package.
6 . The hermetically sealed package of claim 5 , wherein the at least one functional area is formed as a cavity, the at least one accommodation item comprising a power semiconductor chip, which is selected from the group consisting of a GaN light-emitting diode, a SiC power transistor, a GaAs power transistor, and a GaN power transistor, the power semiconductor chip being arranged inside the cavity.
7 . The hermetically sealed package of claim 1 , wherein at least one of:
the cap is welded to the heat-dissipating base substrate at room temperature during a welding process, and wherein only a negligible amount of heat enters the at least one functional area due to the welding process; and
an amount of heat generated by the welding process is kept away from the at least one functional area by the heat-dissipating base substrate.
8 . The hermetically sealed package of claim 1 , wherein the heat-dissipating base substrate and the cap are fused to one another.
9 . The hermetically sealed package of claim 1 , wherein the intermediate substrate which is arranged between the heat-dissipating base substrate and the cap,
wherein the heat-dissipating base substrate is joined to the intermediate substrate in a first bonding plane, and the cap is joined to the intermediate substrate in a second bonding plane.
10 . The hermetically sealed package of claim 9 , wherein the at least one functional area is formed as an accommodation cavity, wherein at least one of:
the cap defines an upper side and a laterally circumferential edge of the at least one functional area, and the heat-dissipating base substrate defines a bottom of the at least one functional area, which together completely enclose the accommodation cavity; and
the cap defines an upper side of the at least one functional area, the intermediate substrate defines a laterally circumferential edge of the at least one functional area, and the heat-dissipating base substrate defines a bottom of the at least one functional area, which together completely enclose the accommodation cavity.
11 . The hermetically sealed package of claim 10 , wherein the hermetically sealed package formed by at least one of the laterally circumferential edge, the bottom, and the upper side is at least partially transparent for a wavelength range.
12 . The hermetically sealed package of claim 1 , wherein at least one of the heat-dissipating base substrate and the cap has a thickness of one of less than 500 μm, less than 300 μm, less than 120 μm, and less than 80 μm.
13 . The hermetically sealed package of claim 1 ,
wherein the heat-dissipating base substrate defines a bottom of the at least one functional area,
wherein the heat-dissipating base substrate has at least a first contact and a second contact, and
wherein the first contact is disposed on the bottom of one of the at least one functional area and a cavity which the at least one functional area forms.
14 . The hermetically sealed package according claim 13 , wherein the second contact is (a) disposed outside the bottom of one of the at least one functional area and the cavity and (b) electrically connected to the first contact.
15 . The hermetically sealed package of claim 1 , wherein at least one of:
wherein the hermetically sealed package has a size of one of no more than 10 mm×10 mm, no more than 5 mm×5 mm, no more than 2 mm×2 mm, and no more than 0.2 mm×0.2 mm;
wherein the cap has a height of no more than 2 mm; and
wherein a skirt of the cap has a height of no more than 2 mm.
16 . The hermetically sealed package of claim 1 , wherein the hermetically sealed package is produced by a method which includes the steps of:
providing that the cap is transparent at least in some portions thereof for at least one wavelength range and therefore is a transparent cap, the at least one functional area including a hermetically sealed accommodation cavity enclosed in the hermetically sealed package, the at least one functional area being surrounded by a laterally circumferential edge, a bottom, and an upper side of the hermetically sealed package, the accommodation cavity being configured for accommodating an accommodation item;
arranging at least one of the accommodation item on the bottom of the accommodation cavity;
arranging the cap on the heat-dissipating base substrate above the accommodation item and thereby creating at least one contact area between the heat-dissipating base substrate and the cap so that the hermetically sealed package has the at least one contact area; and
hermetically sealing the accommodation cavity by forming the at least one laser bonding line along the at least one contact area of the hermetically sealed package.
17 . The hermetically sealed package of claim 16 , wherein the hermetically sealed package is configured for being used as one of a medical implant, a sensor, and a barometer.
18 . The hermetically sealed package of claim 1 , wherein the cap defines an upper side of the at least one functional area, and the heat-dissipating base substrate defines a laterally circumferential edge and a bottom of the at least one functional area, which together completely enclose an accommodation cavity.
19 . A method for providing the hermetically sealed package of claim 1 , the method comprising the steps of:
providing a stack of substrates for forming at least one of the hermetically sealed package, the stack including the heat-dissipating base substrate and the cap, the cap being transparent at least in some portions thereof for at least one wavelength range and therefore being a transparent cap;
arranging an accommodation item on a bottom of an accommodation cavity;
arranging the cap on the heat-dissipating base substrate above the accommodation item and thereby creating at least one contact area between the heat-dissipating base substrate and the cap so that each one of the hermetically sealed package has the at least one contact area; and
hermetically sealing the accommodation cavity by forming the at least one laser bonding line along the at least one contact area of each one of the hermetically sealed package, the hermetically sealed package enclosing the at least one functional area including a cavity, the at least one functional area being surrounded by a laterally circumferential edge, a bottom, and an upper side of the hermetically sealed package, the cavity being the accommodation cavity which is configured for accommodating the accommodation item.
20 . The method of claim 19 ,
wherein the cap comprises a skirt and a top portion, so that the top portion of the cap defines the upper side and the skirt defines at least a part of the laterally circumferential edge of the accommodation cavity; and
wherein the at least one contact area is defined on an end face of the skirt.
21 . The method of claim 19 ,
wherein a laser beam is directed around the at least one functional area to form the at least one laser bonding line so that the at least one functional area is hermetically sealed circumferentially along the at least one contact area;
wherein at least one of (a) the laser beam is directed circumferentially around multiple times and (b) a plurality of laser bonding lines are formed.
22 . The method of claim 19 ,
wherein a plurality of bottoms are defined on the heat-dissipating base substrate for a plurality of accommodation cavities to be provided; and
wherein a plurality of caps are applied to the heat-dissipating base substrate to form a plurality of hermetically sealed packages with respect to the heat-dissipating base substrate.