• Title/Summary/Keyword: poly-si TFT

Search Result 299, Processing Time 0.03 seconds

Design of Poly-Silicon Thin Film Transistor Circuits for Driving Liquid Crystal Display and Analysis of Characteristics of the Devices (액정표시기 구동을 위한 다결정 실리콘 박막 트랜지스터 회로의 설계 및 기초소자 특성분석)

  • 허성회;한철희
    • Journal of the Korean Institute of Telematics and Electronics A
    • /
    • v.31A no.3
    • /
    • pp.39-46
    • /
    • 1994
  • CMOS LCD driving circuits using poly-Si TFT have been designed and basic blocks including test patterns have been fabricated. Column driver drives the pixels by block because polu-Si TFT can not operate at the speed of video signal. Row driver has mode selection circuit which can select a mode between interlacing mode and non-interlacing mode. Experimental results show shift register can operate at 1MHz colck frequency with 4pF load.

  • PDF

Degradation of Polycrystalline Silicon Thin Film Transistor by Inducing Stress (스트레스 인가에 의한 다결정 실리콘 박막 트랜지스터의 열화 특성)

  • 백도현;이용재
    • Proceedings of the IEEK Conference
    • /
    • 2000.06b
    • /
    • pp.322-325
    • /
    • 2000
  • N-channel poly-Si TFT, Processed by Solid Phase Crystalline(SPC) on a glass substrate, has been investigated by measuring its electrical properties before and after electrical stressing. It is observed that the threshold voltage shift due to electrical stress varies with various stress conditions. Threshold voltages measured in 1.5$\mu\textrm{m}$ and 3$\mu\textrm{m}$ poly-Si TFTs are 3.3V, 3.V respectively. With the threshold voltage shia the degradation of transconductance(G$\_$m/) and subthreshold swing(S) is also observed.

  • PDF

A New Level Shifter using Low Temperature poly-Si TFTs

  • Shim, Hyun-Sook;Kim, Jong-Hun;Cho, Byoung-Chul;Kwon, Oh-Kyong
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2004.08a
    • /
    • pp.1015-1018
    • /
    • 2004
  • We proposed a new cross-coupled level shifter circuit using low temperature poly-Si(LTPS) TFT. The proposed level shifter can operate on low input voltage in spite of low mobility and widely varying high threshold voltage of LTPS TFT. Also, the proposed level shifter operates at high frequency and reduces power consumption for having fast rising and falling time and shortening period flowing short-circuit currents.

  • PDF

Performance of Thin Film Transistors Having an As-Deposited Polycrystalline Silicon Channel Layer

  • Hong, Wan-Shick;Cho, Hyun-Joon;Kim, Tae-Hwan;Lee, Kyung-Min
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2007.08b
    • /
    • pp.1266-1269
    • /
    • 2007
  • Polycrystalline silicon (poly-Si) films were prepared directly on plastic substrates at a low (< $200^{\circ}C$) by using Catalytic Chemical Vapor Deposition (Cat-CVD) technique without subsequent annealing steps. Surface roughness of the poly-Si layer and the density of the gate dielectric layer were found to be influential to the TFT performance.

  • PDF

Electrical Characteristics and Leakage Current Mechanism of High Temperature Poly-Si Thin Film Transistors (고온 다결정 실리콘 박막트랜지스터의 전기적 특성과 누설전류 특성)

  • 이현중;이경택;박세근;박우상;김형준
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.11 no.10
    • /
    • pp.918-923
    • /
    • 1998
  • Poly-silicon thin film transistors were fabricated on quartz substrates by high temperature processes. Electrical characteristics were measured and compared for 3 transistor structures of Standard Inverted Gate(SIG), Lightly Doped Drain(LDD), and Dual Gate(DG). Leakage currents of DG and LDD TFT's were smaller that od SIG transistor, while ON-current of LDD transistor is much smaller than that of SIG and DG transistors. Temperature dependence of the leakage currents showed that SIG and DG TFT's had thermal generation current at small drian bias and Frenkel-Poole emission current at hight gate and drain biases, respectively. In case of LDD transistor, thermal generation was the dominant mechanism of leakage current at all bias conditions. It was found that the leakage current was closely related to the reduction of the electric field in the drain depletion region.

  • PDF

Fabrication of excimer laser annealed poly-Si thin film transistor using polymer substrates

  • Kang, Soo-Hee;Kim, Yong-Hoon;Han, Jin-Woo;Seo, Dae-Shik;Han, Jeong-In
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2006.08a
    • /
    • pp.1162-1165
    • /
    • 2006
  • In this paper, the characteristics of polycrystalline silicon thin-film transistors (poly- Si TFTs) fabricated on polymer substrates are investigated. The a-Si films was laser annealed by using a XeCl excimer laser and a four-mask-processed poly-Si TFT was fabricated with fully self-aligned top gate structure. The fabricated nMOS TFT showed field-effect mobility of ${\sim}30\;cm^2/Vs$, on/off ratio of $10^5$ and threshold voltage of 5 V.

  • PDF

The Characterization of Poly-Si Thin Film Transistor Crystallized by a New Alignment SLS Process

  • Lee, Sang-Jin;Yang, Joon-Young;Hwang, Kwang-Sik;Yang, Myoung-Su;Kang, In-Byeong
    • Journal of Information Display
    • /
    • v.8 no.4
    • /
    • pp.15-18
    • /
    • 2007
  • In this paper, we investigated the SLS process to control grain boundary(GB) location in TFT channel region, and it has been found to be applicable for locating the GB at the same location in the channel region of each TFT. We fabricated TFT by applying a new alignment SLS process and compared the TFT characteristics with a normal SLS method and the grain boundary location controlled SLS method. Also, we have analysed degradation phenomena under hot carrier stress conditions for n-type LDD MOSFETs.

Reducing the Poly-Si TFT Nonuniformity by Transistor Slicing (다결정 실리콘 TFT의 불균일도 개선을 위한 트랜지스터 슬라이싱)

  • 이민호;이인환
    • Proceedings of the IEEK Conference
    • /
    • 1999.06a
    • /
    • pp.261-264
    • /
    • 1999
  • This paper presents a circuit-level method to deal with transistor nonuniformity In this method, which is called transistor slicing, a transistor is implemented as a parallel connection of multiple smaller transistors. The paper analyzes the method and demonstrates that transistor slicing can effectively reduce the nonuniformity in TFT mobility and threshold voltage. The method is particularly useful in Implementing analog functions using poly-silicon TFTs which show a significant level of nonuniformity.

  • PDF

A Failure Analysis of SLS Polysilicon TFT Devices for Enhanced Performances (SLS 다결정 실리콘 TFT 소자의 불량분석에 관한 연구)

  • 오재영;김동환;박정호;박원규
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.15 no.11
    • /
    • pp.969-975
    • /
    • 2002
  • Thin film transistors(TFT) were made based on the polycrystalline Si (poly-Si) crystallized by sequential lateral solidification(SLS) method. The electrical characteristics of the devices were analyzed. n-type TFTs did not show a superior characteristics compared to p-type TFTs. We analyzed the causes of the failure by focused ion beam(FIB) analysis and automatic spreading resistance(ASR) measurement, to study the structural integrity and the doping distribution, respectively. FIB showed no structural problems but it revealed a non-intermixed layer in the contact holes between the polysilicon and the aluminum electrode. ASR analyses on poly-Si layer with various doping concentrations and activation temperatures showed that the inadequately doped areas were partially responsible for the inferior behavior of the whole device.