Engineering topics

Petersen, R. C.

Publications and source records attributed to Petersen, R. C..

3 records

NASA NTRS1981

Silicon solar cells with nickel/solder metallization

The use of nickel plus solder is shown to be feasible for contact metallization for silicon solar cells by offering a relatively inexpensive method of making electrical contact with the cell surfaces. Nickel is plated on silicon solar cells using an electroless chemical deposition method to give contacts with good adhesion, and in some cases where adhesion is poor initially, sintering under relatively mild conditions will dramatically improve the quality of the bond without harming the p-n junction of the cell. The cells can survive terrestrial environment stresses, which is demonstrated by a 1000 hour test at 85 C and 85% relative humidity under constant forward bias of 0.45 volt.

Petersen, R. C.↗

NASA NTRS1980

Phase 2 of the array automated assembly task for the low cost silicon solar array project

Studies were conducted on several fundamental aspects of electroless nickel/solder metallization for silicon solar cells. A process, which precedes the electroless nickel plating with several steps of palladium plating and heat treatment, was compared directly with single step electroless nickel plating. Work was directed toward answering specific questions concerning the effect of silicon surface oxide on nickel plating, effects of thermal stresses on the metallization, sintering of nickel plated on silicon, and effects of exposure to the plating solution on solar cell characteristics. The process was found to be extremely lengthy and cumbersome, and was also found to produce a product virtually identical to that produced by single step electroless nickel plating, as shown by adhesion tests and electrical characteristics of cells under illumination.

Petersen, R. C.↗

NASA NTRS1980

Nickel contacts for low cost solar cells

It is noted that nickel metallization of silicon solar cells offers a relatively inexpensive method of making electrical contact with the surface of the cell. More expensive methods, involving precious metals and costly processes, are widely used; these have been developed for space applications, where considerations of reliability predominate over those of cost. Since recent interest in terrestrial applications of solar cells has led to an increased concern over cost, nickel has assumed a position as a major candidate for solar cell metallization. It is shown that sintering can improve the integrity of the nickel-silicon bond. Evidence that the nickel-silicon contact can survive moderate environmental stress is presented.

Anderson, J. R.↗