Novellus Systems Incorporated

Yield Engineering Systems, Inc.

Randy Hall

Peter Krotov

M Ziaul Karim

John Giles Langan

Sooyun Joh

Colin F Smith

William R Entley

The present disclosure is directed to a compact vertical oven for reflow of solder bumps for backend processes in semiconductor wafer assembly and packaging. This disclosure describes a vertical oven which uses a plurality of wafers (e.g., an example value is 50-100 wafers) in a batch with controlled injection of the reducing agent (e.g. formic acid), resulting in a process largely free of contamination. This disclosure describes controlled formic acid flow through a vertical system using laminar flow technology in a sub-atmospheric pressure environment, which is not currently available in the industry. The efficacy of the process depends on effective formic acid vapor delivery, integrated temperature control during heating and cooling, and careful design of the vapor flow path with exhaust. Zone-dependent reaction dynamics managed by vapor delivery process, two-steps temperature ramp control, and controlled cooling process and formic acid content ensures the effective reaction without any flux.

Batch processing oven and method

A solder reflow oven may include a reflow chamber and a plurality of vertically spaced apart wafer-support plates positioned in the reflow chamber. A plurality of semiconductor wafers each including a solder are configured to be disposed in the reflow chamber such that each semiconductor wafer is disposed proximate to, and vertically spaced apart from, a wafer-support plate. Each wafer-support plate may include at least one of liquid-flow channels or resistive heating elements. A control system control the flow of a hot liquid through the channels or activate the heating elements to heat a wafer to a temperature above the solder reflow temperature.

Solder reflow oven for batch processing

In accordance with an embodiment of the present intention, a fluorine residue removing method includes: supplying an oxygen-containing gas and a hydrogen-containing gas into a CVD chamber; producing a plasma of a mixture of the oxygen-containing gas and the-hydrogen containing gas, so that the plasma reacts with the fluorine residue, exothermically generating water; and evacuating from the CVD chamber a product of the reaction between the plasma and the fluorine residue. For the hydrogen-containing gas, NHis often used, and for the oxygen-containing gas, NO, O, or air is used. Exemplary mixtures of the oxygen-containing and the hydrogen-containing gases include 70 mol % NO/NH, 50 mol % NO/NH, and 52 mol % O/NH. An inert gas, such as He, Ne, Ar, or Kr, can be optionally supplied into the chamber to stabilize the plasma.

In situ plasma process to remove fluorine residues from the interior surfaces of a CVD reactor

In one embodiment, a mixing device includes a nozzle that is disposed tangent to a wall of a chamber. Gas flowing from the nozzle rotates in the chamber forming a vortex. Another gas may be flown near a middle portion of the chamber, thereby uniformly mixing the two gases. In another embodiment, an evaporation and mixing device includes a nozzle configured to impart rotation to a gas flowing into a chamber. An injector flows a liquid material near a middle portion of the chamber, thereby mixing the gas and the liquid material. A heater may be employed to help evaporate the liquid material.

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Livermore, CA, United States of America

Randy Hall