Extension of a multilayer interconneciton technology in MCM-Si with opto-electronic facilities

摘要

The increasing I/O-density of today's packages is dealt with by using multilayer modules. Since there is also a trend towards faster interconnections by using optics, the extension of the interconnection module with V-grooves is in high demand. This paper reports on the electro-optical extensions of an earlier develoed standard MCM-Si technology (Lernout et al., Jurnal of IMAPS (Europe) 1998; 15(1): 39-42; Ref. 1). The technology aspects of this stanard MCM-Si technology are presented. The extended thin-film multilayer module is built up using two metal and three insulator layers. Additionally an implementation wiht low TCR resistors (NiCr) can be made. Fiber holding structures, namely V-grooves, are created into the bulk (100) silicon substrate by means of an anisotropic etching, performed in aqueous KOH.A passivation layer of silicon nitride, optimised towards low silicon content, served as protection mask during the KOH etching. The compatibility of this aggressive wet etching step with other processing steps is discussed. As for the insulatiiors in the multilayer module, these high quality PECVD (Plasma Enhanced Chemical Vapour Deposition) layers are optimised towards low stress content and uniformity.