An Assessment of µ-Czochralski, Single-Grain Silicon Thin-Film Transistor Technology for Large-Area, Sensor and 3-D Electronic Integration Nitz Saputra, Student Member , IEEE

Abstract

Single-grain (SG) thin-film transistors (TFTs) fabricated inside location-controlled silicon grains using the -Czochralski method are benchmarked for analog and RF applications. Each silicon grain is defined by excimer laser recrys- tallization of polysilicon. Thin-film transistors may be fabricated in this manner on silicon or low-cost flexible plastic substrates as processing temperatures remain below 350 C, making the SG-TFT a potential enabling technology for large-area highly integrated electronic systems or systems-in-package with low manufacturing cost. Operational amplifier and voltage reference circuits of varying complexity were designed and measured in order to evaluate the effects of channel position and processing variation on analog circuits. A two-stage telescopic cascode oper- ational amplifier fabricated in an experimental 1.5 m SG-TFT technology demonstrates a DC gain of 55 dB (unity-gain band- width of 6.3 MHz), while a prototype CMOS voltage reference with a power supply rejection ratio (PSRR) of 50 dB is also demonstrated. With /84 comparable to single-crystal MOSFETs of comparable gate length, the SG-TFT can also enable RF circuits for wireless applications. A 12 dB gain RF cascode amplifier with on-chip inductors and operating in the 433 MHz ISM band is demonstrated. Excellent agreement with simulations is attained using a modified BSIM-SOI model extracted from measurements of experimental SG-TFT devices.