Ionized metal cluster beam systems and methods
AssigneesMicroelectronics and Computer Technology Corporation, Hughes Aircraft Company
InventorsNalin Kumar, Chenggang Xie, Rama R. Goruganthu, Mohammed K. Ghazi
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Abstract
Ionized metal cluster beam deposition of metal bumps on substrates such as multi-chip modules and integrated circuit chips is enhanced. The present invention discloses wet etching techniques for removing unwanted metal deposited on the substrate around bumps, multiple sources for depositing alloyed (tin-lead) bumps with constant composition, and single or multiple sources for directing a cluster beam through an aperture to deposit metal on a substrate and directing an ion beam at the aperture to remove metal deposited therein.
Claims31
A method of removing metal deposited in a focusing aperture for an ionized metal cluster beam, said method comprising the steps of:
- generating an ionized metal cluster beam;
- providing an aperture holder with a aperture therethrough;
- directing the cluster beam at the aperture holder wherein a portion of the cluster beam enters and passes through the aperture whereas another portion of the cluster beam strikes the aperture holder and deposits metal on the aperture holder, and the deposited metal blocks some or all of the aperture;
- discontinuing to direct the cluster beam at the aperture;
- generating an ion beam;
- directing the ion beam at the aperture so that at least some of the deposited metal blocking the aperture is removed;
- discontinuing to direct the ion beam at the aperture;
- and then
- directing a portion of the cluster beam at the aperture, thereby preventing the deposited metal from completely blocking the aperture.
A system for removing metal deposited in a focusing aperture for an ionized metal cluster beam, the system comprising:
- an aperture holder with an aperture therethrough;
- a source for generating an ionized metal cluster beam capable of directing the cluster beam at the aperture holder so that a portion of the cluster beam enters and passes through the aperture whereas another portion of the cluster beam strikes the aperture holder and deposits metal thereon such that deposited metal blocks some or all of the aperture;
- and
- a source for generating an ion beam capable of directing the ion beam at the aperture so that the ion beam removes at least some of the deposited metal which blocks the aperture, thereby preventing the deposited metal from completely blocking the aperture.
Dependencies are inferred from the claim text.