The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 16, 1999
Filed:
Jul. 12, 1996
King-Ning Tu, Los Angeles, CA (US);
Jia-Sheng Huang, Los Angeles, CA (US);
The Regents of the University of California, Oakland, CA (US);
Abstract
Dopant activation in heavily boron doped p.sup.+ --Si is achieved by applying electric current of high density. The p.sup.+ --Si was implanted by a 40 KeV BF.sup.2+ at an ion intensity 5.multidot.10.sup.15 ions per cm.sup.2 and annealed at 900.degree. C. for 30 minutes to obtain a partial boron activation according to conventional processing steps. To obtain additional activation and higher conductivity, current was gradually applied according to the invention to a current density of approximately 5.times.10.sup.6 A/cm.sup.2 was realized. The resistance of the p.sup.+ --Si gradually increases and then decreases with a precipitous drop at a threshold current. The resistance was reduced by factor of 5 to 18 times and was irreversible if an activation current threshold was reached or exceeded. The high-current-density-dopant activation occurs at room temperature.