Impact ionization-induced bistability in CMOS transistors at cryogenic temperatures for capacitorless memory applications.

Cryogenic operation of complementary metal oxide semiconductor (CMOS) silicon transistors is crucial for quantum information science, but it brings deviations from standard transistor operation. Here, we report on sharp current jumps and stable hysteretic loops in the drain current as a function of gate voltage V G for both n- and p-type commercial-foundry 180-nm-process CMOS transistors when operated at voltages exceeding 1.3 V at cryogenic temperatures. The physical mechanism responsible for the device bistability is impact ionization charging of the transistor body, which leads to effective back-gating of the inversion channel. This mechanism is verified by independent measurements of the body potential. The hysteretic loops, which have a >107 ratio of high to low drain current states at the same V G, can be used for a compact capacitorless single-transistor memory at cryogenic temperatures with long retention times.

Anti-Ata causing mild hemolytic disease of the newborn.

We report here a case of moderately severe hemolytic disease of the newborn (HDN) due to anti-Ata. The gravida 5 proposita was group A rr and previously was found to have anti-Ata and -D. At the 35-week mark of this pregnancy, her anti-Ata demonstrated a titer of 256, score 79. Fluid obtained by amniocentesis at 36 weeks showed an optical density at 450 nm of 0.08 (midzone). The baby was delivered at 38 weeks by cesarean section. The cord cells were group A rr with a 3+ direct antiglobulin test. The dichloromethane eluate of the infant's cells demonstrated anti-Ata specificity only. At birth, the infant's total bilirubin (TB) was 2.1 mg per dl and the hematocrit level (Hct) was 33.8 percent. Within 8 hours, the TB had risen to 3.8 mg per dl. Phototherapy was initiated at 7-1/2 hours and maintained for 40 hours. The infant's TB rose to a maximum level of 10.5 mg per dl 24 hours after phototherapy was discontinued. At discharge 4 days postpartum, the infant's TB had dropped to 9.2 mg per dl, and the Hct value was 38 percent. On a visit 7 days postpartum, the infant's TB level had fallen to 6.5 mg per dl and the hct value was 38 percent. Transfusions were not necessary.