Wafer level chip scale packaging with sensor
The present disclosure is directed to a package (e.g., a chip scale package, a wafer level chip scale package (WLCSP), or a package containing a sensor die) with a sensor die on a substrate (e.g., an application-specific integrated circuit die (ASIC), an integrated circuit, or some other type of die having active circuitry) and encased in a molding compound. The sensor die includes a sensing component that is aligned with a centrally located opening that extends through the substrate. The centrally located opening extends through the substrate at an inactive portion of the substrate. The centrally located opening exposes the sensing component of the sensor die to an external environment outside the package.
1 . A device, comprising:
a first die including a first surface, a second surface opposite to the first surface, sidewalls extending between the first surface and the second surface, and an opening extending through the first die from the first surface to the second surface, the opening extending through a central portion of the first die and including at least one sidewall that delimits the opening, the first die having a first ring-contact that surrounds the opening and one or more first contact pads that are spaced laterally outward from the first ring-contact;
a space extending outward from the at least one sidewall of the opening towards the sidewalls of the first die;
a second die being on the first die, the second die including a third surface, a fourth surface opposite to the third surface, one or more sidewalls extending form the third surface to the fourth surface, and a sensing component at the third surface being aligned with the opening in the first die, the second die having a second ring-contact that surrounds the sensing component and that is aligned with the first ring-contact of the first die and one or more second contact pads spaced laterally outward from the second ring-contact, and each respective second contact pad of the one or more second contact pads is aligned with a respective first contact of the one or more first contact pads;
a molding compound being on the third surface of the second die and between the first die and the second die, the molding compound being on the one or more sidewalls of the second die;
a conductive ring-structure that extends from the first ring-contact to the second ring-contact and couples the first ring-contact to the second ring-contact, the conductive ring-structure surrounds the first opening; and
one or more conductive structures that couple the one or more first contact pads to the one or more second contact pads, the one or more conductive structures being spaced outward from the conductive ring-structure.
2 . The device of claim 1 , wherein the molding compound is on the conductive ring-structure, the surface of the conductive ring-structure is between the first surface of the first die and the third surface of the second die.
3 . The device of claim 1 , wherein the first ring-contact on the first surface of the first die is coupled to an electrical connection that extends through the first die to the second surface of the first die.
4 . The device of claim 1 , wherein the opening has a first dimension between a first sidewall and a second sidewall of the sidewalls of the first die, the second sidewall being opposite to the first sidewall, the sensing component has a second dimension between a third sidewall and a fourth sidewall of the second die, the fourth sidewall being opposite to the third sidewall, and the first dimension is greater than the second dimension.
5 . The device of claim 1 , wherein the sensing component is a pressure sensor that includes a surface that is spaced from the third surface of the second die.
6 . The device of claim 1 , wherein:
the opening has a first dimension that is between opposing points along the at least one sidewall that delimits the opening; and
the sensing component has a second dimension, and the first dimension is greater than the second dimension.
7 . The device of claim 1 , wherein the one or more conductive structures are one or more solder balls.
8 . The device of claim 2 , wherein:
the conductive ring-structure includes a first side and a second side, the first side is closer to the opening than the second side; and
the molding compound physically contacts and at least partially covers the second side of the conductive ring-structure.
9 . A device, comprising:
a first die including an opening extending through a central portion of the first die, the first die further including:
a first surface;
a second surface opposite to the first surface;
a plurality of first contacts on the first surface; and
a first ring-contact that is between the first plurality of contacts and the opening, the first ring-contact is spaced laterally inward from the plurality of first contacts, and the first ring-contact surrounds the opening;
a second die on the first die, the second die including a sensing component aligned with the opening in the first die, the second die further including:
a third surface;
a fourth surface opposite to the third surface;
a plurality of second contacts on the third surface, each respective second contact of the plurality of second contacts is aligned with a corresponding first contact of the plurality of first contacts;
one or more sidewalls extending from the third surface to the fourth surface; and
a second ring-contact that is between the plurality of second contacts and the sensing component, the second ring-contact is spaced laterally inward from the plurality of second contacts, the second ring-contact is aligned with the first ring-contact, and the second ring-contact surrounds the sensing component;
a plurality of solder balls couple the first plurality of contacts to the second plurality of contacts, each respective solder ball of the plurality of solder balls couple each respective first contact of the plurality of first contacts to a corresponding second contact of the plurality of second contacts;
a ring-solder structure is between the first die and the second die, the ring-solder structure couples the first ring-contact to the second ring-contact, and the ring-solder structure is between the opening of the first die and the plurality of solder balls; and
a molding compound being on the third surface of the second die and between the first die and the second die, the molding compound being on the one or more sidewalls of the second die, the molding compound enclosing the plurality of solder balls, and the molding compound contacting the ring-solder structure.
10 . The device of claim 9 , wherein the sensing component is a pressure sensor that includes a surface that is spaced from the third surface of the second die.
11 . The device claim 9 , further comprising a space extending between the first surface and the third surface and extending between the ring-solder structure and the opening, the space surrounding the opening and the sensing component, and the space being in fluid communication with the opening.
12 . The device of claim 9 , wherein:
the opening has a first dimension extending across the opening;
the sensing component has a second dimension extending across the sensing component;
the space having a third dimension extending across the space and between the ring-solder structure;
the first dimension being greater than the second dimension; and
the third dimension being greater than the first dimension and the second dimension.
13 . The device of claim 9 , wherein the first die includes an inactive region at the central portion of the first die, the opening having a first dimension extending across the opening, the inactive region having a second dimension extending across the inactive region, the second dimension being greater than the first dimension.
14 . The device of claim 9 , wherein the sensing component is a moveable electrode.
15 . A device, comprising:
a first die including a first surface, a second surface opposite to the first surface, one or more outer sidewalls extending between the first surface and the second surface, and an opening extending through the first die from the first surface to the second surface, the opening extending through a central portion of the first die and including at least one inner sidewall that delimits the opening, the at least one inner sidewall being spaced inward from the one or more outer sidewalls, the first die including a first ring-contact that is along the first surface and that surrounds the opening, the first die including a plurality of first contact pads along the first surface, each respective first contact pad of the plurality of first contact pads is spaced laterally outward from the first ring-contact, and the first die includes a non-conductive layer along the first surface, and the first die including a first sidewall transverse to the first surface and the second surface, and the first sidewall is partially defined by the non-conductive layer;
a second die being on the first die, the second die including a third surface, a fourth surface opposite to the third surface, one or more sidewalls extending form the third surface to the fourth surface, and a sensing component at the third surface being aligned with the opening in the first die, the second die including a second ring-contact that is along the third surface and that surrounds the sensing component, the second ring-contact is aligned with the first ring-contact of the first die, the second die including a plurality of second contact pads along the third surface, each respective second contact pad of the plurality of second contact pads is spaced laterally outward from the second ring-contact, and each respective second contact pad of the plurality of second contact pads is aligned with a corresponding first contact pad of the plurality of first contact pads;
a solder ring-structure extends from the first ring-contact to the second ring-contact and couples the first ring-contact to the second ring-contact, the solder ring-structure includes a first side further from the opening and a second side close to the opening;
a space extending outward from the at least one inner sidewall of the opening towards the one or more outer sidewalls of the first die and extends to the solder ring-structure, the space being delimited by the first surface of the first die, third surface of the second die, and the solder ring-structure;
a plurality of solder balls between the first surface of the first die and the second surface of the second die, the plurality of solder balls couple the plurality of first contact pads to the plurality of second contact pads; and
a molding compound being on the third surface of the second die and between the first die and the second die, the molding compound being on the one or more sidewalls of the second die, the molding compound including a second sidewall coplanar with the first sidewall of the first die, the molding compound enclosing the plurality of solder balls, and the molding compound covering the first side of the solder ring-structure.
16 . The device of claim 15 , wherein the first ring-contact, the second ring-contact, and the solder ring-structure have a rectangular shape.
17 . The device of claim 16 , wherein the rectangular shape is a square shape.
18 . The device of claim 16 , wherein the first ring-contact on the first surface of the first die is coupled to an electrical connection that extends through the first die to the second surface of the first die.
19 . The device of claim 18 , further includes an external contact pad that is on the second surface of the first die and is coupled to the electrical connection.
20 . The device of claim 15 , wherein the first ring-contact on the first surface of the first die is coupled to an electrical connection that extends through the first die to the second surface of the first die.