Motorola Corporation

Freescale Semiconductor,inc.

Clem H Brown

John E Salina

Wai Wong Chow

David L Vowles

Zhi-Gang Bai

Daniel J Wallace, Jr

Vasile Romega Thompson

Frank J Mosna, Jr

Mario F Velez

A semiconductor package () includes an organic substrate () and a semiconductor die subassembly (). A method () for making the semiconductor package () entails providing () the organic substrate () having an opening () and electrical contacts (). The subassembly () is formed by producing () a semiconductor die () and bonding it to a platform layer (). An elastomeric adhesive () is utilized () to secure the subassembly () in the opening (). Electrical interconnects () are provided () between the semiconductor die () and the electrical contacts () of the organic substrate (). The organic substrate (), semiconductor die (), elastomeric adhesive (), and electrical interconnects () are encapsulated () in a packaging material (). The elastomeric adhesive () provides mechanical anchoring of the subassembly () to the substrate () and provides mechanical stress isolation of the semiconductor die () within the semiconductor package ().

Semiconductor package with mechanical stress isolation of semiconductor die subassembly

A leadframe () for a semiconductor device includes a first leadframe portion () having a perimeter that defines a cavity () and a plurality of leads () extending inwardly from the perimeter and a first thickness. A second leadframe portion () is attached to the first leadframe portion (). The second leadframe portion () has a die paddle () received within the cavity () of the first leadframe portion (). The second leadframe portion () has a second thickness that is greater than a thickness of the first leadframe portion (). Such a dual gauge leadframe is suitable especially for high power devices in which the die paddle acts as a heat sink.

Method for making dual gauge leadframe

A semiconductor component for electrical coupling to a substrate () includes: a semiconductor chip (); a non-leaded leadframe () including a plurality of electrical contacts () located around a periphery () of the semiconductor chip; a first electrical conductor () electrically coupling together the semiconductor chip and the non-leaded leadframe; and a mold compound () disposed around the semiconductor chip, the first electrical conductor, and the plurality of electrical contacts. At least one electrical contact of the plurality of electrical contacts includes: a first surface () having a first surface area for electrically coupling to the semiconductor chip; and a second surface () opposite the first surface and having a second surface area for electrically coupling to the substrate, where the second surface area is larger than the first surface area.

Semiconductor component having first surface area for electrically coupling to a semiconductor chip and second surface area for electrically coupling to a substrate, and method of manufacturing same

Dual gauge leadframe

A differential pressure sensor (10) has a sensor die (30) eutectically attached to a mounting flag (14). The mounting flag has a similar coefficient of thermal expansion to the sensor die. The eutectic attachment provides a hermetic seal between the mounting flag and the sensor die. Pressure is applied to sensor die port (20). A molded housing (12) is molded around the sensor die-mounting flag assembly. Port (22) in the molded housing is filled with a silicone gel (52). A second pressure source is transferred by way of the silicone gel to the sensor die. Any media entering port (20) contacts the first surface of the sensor die to assert pressure against a piezoresistive transducer circuit (32) to generate the electrical signals representative of the applied pressure but are isolated from the sensitive interconnects by the hermetic seal.

Differential pressure sensor and method thereof

A leadframe (10) architecture provides placement of multiple optocoupler pair devices (45, 50) in a minimum size footprint package. A detector flag (20) and LED flag (12) are placed on a common centerline (26) within the footprint. A critical length is determined for packaging factors lying along the centerline. The angle (28) formed between the centerline and the longitudinal axis (24) controls the optocoupler pair fit within the package. The angle (28) is calculated by taking the arc-sine function of the critical length divided by the footprint width.

Small outline optocoupler package method

An optocoupler package (40) has two pre-molded thermoplastic halves (42, 54); one containing the emitter (16) and the other containing the detector (18). The detector half (54) has a well (56) where the detector (54) is located. The well (56) is filled with silicon die coat gel (24). The emitter half (42) has a similar well (48) containing the emitter. Surrounding the well (48) of the emitter half is a protruding wall (50) with relief vents (52). The wall (50) is configured to fit into the perimeter of the well (56) of the detector package half (54). When the package (40) is assembled, the protruding wall (50) of the emitter half (42) is inserted into the well (56) of the detector package half (54), thereby displacing the gel (24) so as to completely fill the internal chamber (66) and spill into the relief vents (52).

Optocoupler package and method for making

Dual channel small outline optocoupler package and method thereof

An electronic pressure sensor (10) is enhanced by attaching a sensor die (18) to a stress isolation platform (12) using an adhesive (42) having a similar thermal coefficient of expansion. The adhesive provides a hermetic seal between the stress isolation platform and the pressure sensor die. A via (20) in the stress isolation platform provides an opening for pressure to be applied to the sensor die. The stress isolation platform is attached to a plastic package body (16) via a semi-rigid adhesive (40) for providing stress isolation and a hermetic seal between the package body and the stress isolation platform. Any hostile chemical entering the via contacts an exposed diaphragm (50) of the sensor die to assert pressure against its piezoelectric network (52) to generate the electrical signals representative of the applied pressure but are kept away from the sensitive interconnects by the hermetic seals.

Pressure sensor with stress isolation platform hermetically sealed to

A differential pressure sensor (10) has a sensor die (16) attached to a stress isolation package base (12) with a bonding glass (27) having a similar coefficient of thermal expansion. The bonding glass, and alternately an aluminum layer, provides a hermetic seal between the stress isolation base and sensor die. Pressure is applied to the sensor die port (24). A plastic housing (14) is attached to the stress isolation base with an adhesive (29). A port (23) in the plastic housing is filled with a silicone gel (22). A second pressure source is transferred by way of the silicone gel to the sensor die. Any hostile chemical entering the via contacts the first surface of the sensor die to assert pressure against a transducer circuit (25) to generate the electrical signals representative of the applied pressure but are isolated from the sensitive interconnects by the hermetic seal.

Hermetically sealed pressure sensor and method thereof

A pressure sensor package (10) has a sensor body (12) for containing a pressure sensor. An elongated stem (14) has a first end connected to the sensor body (12), and a connector (24, 26) is disposed on a second end of the stem (14) for fixedly mounting the stem (14) to a mounting base (40), which is connected to, for example, a fuel tank (52). An annular sealing surface (28) is disposed on the first end of the stem (14) for pressing against a compressible seal (44) when the stem (14) is mounted to the mounting base (40), and an orifice (18) is disposed at the second end of the stem (14). The orifice 18 is connected to the pressure sensor by a passage (20, 22) through the stem body. The connector (24, 26) is spaced a sufficient distance from the sensor body (12) to substantially reduce error-inducing stresses on the pressure sensor.

Pressure sensor package for reducing stress-induced measurement error

A dual absolute pressure sensor independently converts first and second external pressures to first and second electrical signals respectively. A package body has first and second openings for receiving the first and second external pressures to outside surfaces of first and second sensor die attached to opposite surfaces of an internal glass substrate that separates the first and second openings. The first sensor die includes a first cavity having a reference pressure to measure against the first external pressure and develop a first differential pressure. A first piezoelectric network converts the first differential pressure to the first electrical signal representative of that pressure. The second sensor die includes a second cavity having a reference pressure to independently measure against the second external pressure and develop a second differential pressure. A second piezoelectric network converts the second differential pressure to the second electrical signal representative of that pressure.

Dual absolute pressure sensor and method thereof

An optocoupler package made up from a pre-assembled package having a leadframe, a voltage isolation barrier, and a body molded from a reflective plastic material. The voltage isolation barrier is fabricated as part of the body and positioned in such a way as to substantially increase the electrical flashover path between the optical source and the optical detector. An optical source mounted in the pre-assembled package subsequent to fabrication of the molded body. An optical detector is optically coupled to the optical source by reflection within the pre-assembled package, the optical detector being mounted in the pre-assembled package subsequent to fabrication of the molded body A reflective plastic cover is bonded to the pre-assembled package.

Optocoupler package wth integral voltage isolation barrier

A technique for encapsulating an optocoupler apparatus to improve light coupling efficiency, reliability and cost. An optocoupler apparatus comprises a light emitting device (10) and a light detecting device (11) mounted to conductors (12A,12B). A light coupling material (14) surrounds the optocoupler apparatus. The light coupling material (14) is an electrical dielectric which is transparent to light. A portion of the light coupling material (14) is coated with a light reflective material (16). The light reflective material (16) is a mixture of the light coupling material (14) and titanium dioxide. The benefit of coating the light coupling material (14) with the light reflective material (16) is the two materials have similar chemical properties, and the reflective property of the light reflective material (16) arises from the titanium dioxide; the second most reflective material available. An encapsulating material (17 or 19) further envelops the encased optocoupler apparatus.

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Scottsdale, AZ, United States of America

Clem H Brown