Pedestal guard ring having continuous M1 metal barrier connected to crack stop

A microelectronic element, e.g., a semiconductor chip having a silicon-on-insulator layer ("SOI layer") separated from a bulk monocrystalline silicon layer by a buried oxide (BOX) layer in which a crack stop extends in first lateral directions at least generally parallel to the edges of the chip to define a ring-like barrier separating an active portion of the chip inside the barrier with a peripheral portion of the chip. The crack stop can include a first crack stop ring contacting a silicon portion of the chip above the BOX layer; the first crack stop ring may extend continuously in the first lateral directions to surround the active portion of the chip. A guard ring ("GR") including a GR contact ring can extend downwardly through the SOI layer and the BOX layer to conductively contact the bulk monocrystalline silicon region, the GR contact ring extending at least generally parallel to the first crack stop ring to surround the active portion of the chip. A continuous metal ring extending continuously in the first lateral directions can surround the active portion of the chip, such metal ring connecting the GR contact ring with the first crack stop ring such that the metal line and the GR contact ring form a continuous seal preventing mobile ions from moving between the peripheral and active portions of the chip.