  Cryogenic versions of Resistive WELL (RWELL) and Resistive Plate WELL
(RPWELL) detectors have been developed, aimed at stable avalanche
multiplication of ionization electrons in dual-phase TPCs. In the RWELL, a thin
resistive layer deposited on top of an insulator is inserted in between the
electron multiplier (THGEM) and the readout anode; in the RPWELL, a resistive
plate is directly coupled to the THGEM. Radiation-induced ionization electrons
in the liquid are extracted into the gaseous phase. They drift into the THGEM's
holes where they undergo charge multiplication. Embedding resistive materials
into the multiplier proved to enhance operation stability due to the mitigation
of electrical discharges - thus allowing operation at higher charge gain
compared to standard THGEM (a.k.a. LEM) multipliers. We present the detector
concepts and report on the main preliminary results.
