At&t Bell Laboratories

American Telephone and Telegraph, Co.

John W Benko

Alexander Coucoulas

Jerome Levkoff

Daniel C Sutryn

Montri Viriyayuthakorn

Thaddeus Wojcik

Ram J Arvikar

In an MOCVD reactor, gases are channeled around the periphery of a baffle plate (15) so as to flow radially inwardly along a slotted injection plate (16). The slots (22) in the injection plate extend radially and are of non-uniform width so as to compensate for a non-uniform rate of deposition. The resultant flow over a rotating heated substrate (17) gives a more uniform deposit of epitaxially grown material.

MOCVD method and apparatus

An electronic device (10) is surface mounted to bonding pads (11) of a substrate (12) by first mounting the device within an aperture (24) of a glass plate (17). The leads (14) of the electronic device are coated with solder and pressed onto the bonding pads by the reusable glass plate (17). While pressing the plate against the leads, the plate is scanned with a laser beam (16) directly over each row of bonding pads. The laser light is of an appropriate wavelength such that the glass plate converts the laser light to heat, which melts the solder to bond the leads to the bonding pads.

Laser soldering method and apparatus

An electronic device package is made by first making in a stencil member (11) an opening (12) in the shape of a closed loop that surrounds an inner portion (13) of the stencil member. The closed loop is a continuous opening except for a plurality of web members (15), each of which extends across the opening to secure the inner stencil portion to the remainder of the stencil member. A glass slurry (7) is forced through the opening of the stencil member onto a first substrate (18) so as to form on the substrate a substantially closed loop of glass slurry, which is thereafter glazed to form a glass loop (32) bonded to the first substrate. The first substrate is used as cover plate and placed over a second substrate (24) containing an electronic device (23) such that the glass loop surrounds the electronic device and contacts the second substrate along its entire length. The glass is heated sufficiently to soften it and cause it to bond to the second substrate as well as the first substrate. Cooling of the glass loop develops continuous hermetic seals to both first and second substrate, thereby to isolate the electronic device from the external environment.

Method for hermetically sealing electronic devices

In one embodiment (FIG. 1) leads (14) are soldered to bonding pads (11) by heating a silica heating member (17) with a laser beam (16). The heating member has a tubular shape and encloses the solder elements to be heated. In another embodiment (FIG. 3), the heating element is a plate (22) overlying elements to be soldered which plate is scanned by a laser beam (28) along a line (31) in close proximity to the elements to be soldered.

Growing community of inventors

Trenton, NJ, United States of America

John W Benko