Apparatus for removing deposited matter from a diffusion tube
US4294271A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 30, 1979 |
| Grant date | Oct 13, 1981 |
| Priority date | — |
| Expiry date | Nov 30, 1999 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S134/902
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
Apparatus for removing deposited matter, such as silicon and contaminants, from the interior of quartz diffusion tubes including an acid holding tank; a quartz-tube support for vertically holding the tube, neck down; a flexible seal for connecting the neck of the tube to the holding tank; an immersion pump and associated tubing for circulating the acid; and a spray head, connected with the pump and tubing, to spray the acid against the inside surface of the quartz tube to clean off the deposited matter. In order to prevent the acid sprayed on the inside surface from forming channels in the silicon or other deposited matter, two groups of nozzles are provided in the spray head--one group with its nozzles arranged at about 30.degree. from vertical, the other group with its nozzles arranged at about 60.degree. from vertical--so that the jets sprayed from each of the two groups are directed 90.degree. from one another; a diverter valve alternately connects the two groups of nozzles to the pump; as the flow of acid is switched from one group of nozzles to the other, the jets of acid are caused to sweep from the direction of one group of nozzles to that of the other, and no channelizatio…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.