Abstract: A method for estimating a time delay including the steps of first, estimating a channel spectrum from a received signal and a known reference signal, second, extracting a virtual array structure from the estimated channel spectrum, and third, determining the signal time delay using the virtual array structure. Further, a system for estimating a time delay including a channel spectrum estimator, means for extracting a virtual array structure and means for determining the time delay is provided. The channel spectrum estimator is used for estimating a channel spectrum from a received signal and a known reference signal. The means for extracting a virtual array structure uses the estimated channel spectrum. The means for determining the time delay uses the virtual array structure.

Abstract: A lead (10) for a semiconductor device (12) comprising a strip portion (14) comprising a first substantially horizontal portion (18) connected to the semiconductor device (12), a substantially vertical portion (20) connected to the first substantially horizontal portion (18), and a second substantially horizontal portion (22) connected to the substantially vertical portion (20) with at least one hole (16) disposed in the strip portion (14). A method of providing an electrical contact for connecting a semiconductor device (12) to a surface (24) comprising the steps of extending at least one lead (10) from the semiconductor device (12) and slotting the lead (10).

Abstract: A removable tab process whereby tabs (7) are affixed to the pads (3) by initially having the bonding surface as flat as possible so that bonding pressures from pad to pad are relatively uniform. Bonding is performed with the pressure applied to the pads being such that the tabs can later be easily removed without damage to the die pads, yet sufficiently strong so that the tabs do not come loose during burn in and testing. A bond strength pull between about 5 and about 40 grams per pad is appropriate for this purpose. The tabs are removed by placing the tested die (1) and attached tabs in a fixture (11) and providing a tool (31) dimensioned and moved along a path (13, 15, 17, 19) whereby each of the tabs is serially removed with the pressure applied to each tab to provide removal being preferably no greater than 40 grams.

Abstract: A light beam is passed through a tube containing a material being monitored and a contaminant wherein the light is absorbed by the contaminant or some form of the contaminant to the exclusion of the material being monitored. Since the amount of light passing through the tube is a function of the amount of contaminant in the tube, the amount of light detected at the downstream end of the tube is a function of the amount of contaminant in the material being monitored. The detected light can be used to provide a quantitative indication of the contaminant, to provide an alarm, to shut down the system to which the material being monitored is being delivered or for other purposes. When the material being monitored is HCl gas and the contaminant is moisture, the tube will generally be stainless steel to avoid galvanic effects since the remainder of the pipe system is generally also stainless steel and the light frequency will be from about 1.0 to about 2.

Abstract: Methods are providing for cleansing contaminants from substrates, such as semiconductor wafer handling implements, and thereby reduce the incidence of contamination of semiconductor devices being assembled upon the semiconductor wafers. In one aspect of the invention, a substrate such as a semiconductor cassette or other semiconductor wafer handling implement, is inserted into a chamber that is substantially isolated from a surrounding environment. A pressurized, and optionally purified, cleansing medium is directed against at least one surface of the substrate to dislodge contaminants from the substrate surface. Dislodged contaminants are evacuated with negative pressure from the chamber. In a preferred aspect of the invention, the cleansing medium is an inert gas, such as nitrogen, and is applied to the substrate at a pressure from about 10 p.s.i. to about 100 or more p.s.i.