Chapter 5 Future Work
5.1 Temperature and Gate Voltage Stress Modulation
In our experiments, we investigated the ISFET’s reliability with temperature and gate voltage stress modulation individual. Therefore, how to link these factors influence range about temperature and gate voltage stress modulation together, and how to control the substrate voltage to make drift voltage become zero for each membrane gate ISFET, and how to design the circuit to realize our idea.
At present, the temperature hysteresis of the gate ISFET is not investigate deeply, and how to reduce it will be study more necessary. A perfect model of gate voltage stress with drift voltage should also be built in the future.
References
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[18] G. T. Yu, “Hydrogen ion diffusion coefficient of silicon nitride thin films”, Applied Surface Science 202, pp. 68-72, 2002.
[19] Y. Vlasov, “Investigation of pH-sensitivity ISFETs with oxide and nitride membranes using colloid chemistry method”, Sensors and Actuators B, 1 pp. 357–360, 1990.
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Fig. 2-1 Electrode and electrolyte interface
(a) (b)
Fig. 2-2 Schematic representation of (a) MOSFET, (b) ISFET
Fig. 2-3 Schematic representation of the site-binding model
Drain Source Gate
electrolyte
Fig. 2-4 ID-VG characteristic of MOSFET and ISFET in different temperatures.
Fig. 2-5 ID-VG characteristic of MOSFET in different temperatures.
Isothermal point
Fig. 2-6 ID-VG characteristic of ISFET in different temperatures.
(a) (b)
Fig. 2-7 Series combination of the (a) initial (b) hydrated insulator capacitance
Silicon
Thermal Oxide Sensing Layer Solution
Hydration
(a)
(b)
`
(c)
(d) Si substrate Wet oxide
Si substrate BOE wet-etching
Si substrate S/D implant
Screen Oxide
PE Oxide
(e)
(f)
(g)
(h) Dry Oxide
Sensing layer 1
Sensing layer 2
(i)
Fig. 3-1 Corresponding graph for fabricate process flow.
Fig. 3-2 Shows the set up of measurement with the HP4156A Semiconductor Parameter Analyzer at room temperature.
Source
Drain Drain
Al electrode
Fig. 3-3 ID-VD curve of the 300Å ZrO2-gate ISFET.
Fig. 3-4 ID-VD curve of the 300Å Ta2O5-gate ISFET.
Fig. 3-5 ID-VD curve of the 300Å Thermal Oxide-gate ISFET.
Fig. 3-6 ID-VD curve of the 300Å PE Oxide-gate ISFET.
Fig. 3-7 Shows the set up of measurement with the HP4156A Semiconductor Parameter Fig. 3-8 Detection principle of different VG.
0
Fig. 4-1 ID-VG curves of the ZrO2 gate ISFET in pH=1, 3, 5, 7 buffer solutions at 25℃.
Fig. 4-2 Sensitivity of the ZrO2 gate ISFET in pH=1, 3, 5, 7 buffer solutions at 25℃.
Fig. 4-3 ID-VG curves of the ZrO2 gate ISFET in pH=1, 3, 5, 7 buffer solutions at 35℃.
Fig. 4-4 Sensitivity of the ZrO2 gate ISFET in pH=1, 3, 5, 7 buffer solutions at 35℃.
Fig. 4-5 ID-VG curves of the ZrO2 gate ISFET in pH=1, 3, 5, 7 buffer solutions at 45℃.
Fig. 4-6 Sensitivity of the ZrO2 gate ISFET at pH=1, 3, 5, 7 buffer solutions at 45℃.
Fig. 4-7 ID-VG curves of the ZrO2 gate ISFET in pH=1, 3, 5, 7 buffer solutions at 55℃
Fig. 4-8 Sensitivity of the ZrO2 gate ISFET at pH=1, 3, 5, 7 buffer solutions at 55℃.
Fig. 4-9 ID-VG curves of the ZrO2 gate ISFET in pH=1, 3, 5, 7 buffer solutions at 65℃.
Fig. 4-10 Sensitivity of the ZrO2 gate ISFET in pH=1, 3, 5, 7 buffer solutions at 65℃.
Fig. 4-11 ID-VG curves of the ZrO2 gate ISFET in pH=1, 3, 5, 7 buffer solutions at 75℃.
Fig. 4-12 Sensitivity of the ZrO2 gate ISFET in pH=1, 3, 5, 7 buffer solutions at 75℃.
Fig. 4-13 ID-VG curves of the ZrO2 gate ISFET in pH=1, 3, 5, 7 buffer solutions at 85℃.
Fig. 4-14 Sensitivity of the ZrO2 gate ISFET in pH=1, 3, 5, 7 buffer solutions at 85℃.
Fig. 4-15 Temperature sensitivity and correlation coefficient dependency of the ZrO2
gate ISFET.
Fig. 4-16 Normalize the temperature sensitivity curve of the ZrO2 gate ISFET.
Fig. 4-17 ID-VG curves of the ZrO2 gate ISFET in pH=1 buffer solution at temperatures of 25℃, 35℃, 45℃, 55℃, 65℃, 75℃, and 85℃.
Fig. 4-18 ID-VG curves of the ZrO2 gate ISFET in pH=3 buffer solution at temperatures of 25℃, 35℃, 45℃, 55℃, 65℃, 75℃, and 85℃.
Fig. 4-19 ID-VG curves of the ZrO2 gate ISFET in pH=5 buffer solution at temperatures of 25℃, 35℃, 45℃, 55℃, 65℃, 75℃, and 85℃.
Fig. 4-20 ID-VG curves of the ZrO2 gate ISFET in pH=7 buffer solution at temperatures of 25℃, 35℃, 45℃, 55℃, 65℃, 75℃, and 85℃.
Fig. 4-21 Iso-thermal point range of the ZrO2 gate ISFET in pH=1, 3, 5, 7 buffer solutions.
Fig. 4-22 ID-VG curves of the Ta2O5 gate ISFET in pH=1, 3, 5, 7 buffer solutions at 25℃.
Fig. 4-23 Sensitivity of the Ta2O5 gate ISFET in pH=1, 3, 5, 7 buffer solutions at 25℃.
Fig. 4-24 ID-VG curves of the Ta2O5 gate ISFET in pH=1, 3, 5, 7 buffer solutions at 35℃.
Fig. 4-25 Sensitivity of the Ta2O5 gate ISFET in pH=1, 3, 5, 7 buffer solutions at 35℃
Fig. 4-26 ID-VG curves of the Ta2O5 gate ISFET in pH=1, 3, 5, 7 buffer solutions at 45℃.
Fig. 4-27 Sensitivity of the Ta2O5 gate ISFET in pH=1, 3, 5, 7 buffer solutions at 45℃.
Fig. 4-28 ID-VG curves of the Ta2O5 gate ISFET in pH=1, 3, 5, 7 buffer solutions at 55℃.
Fig. 4-29 Sensitivity of the Ta2O5 gate ISFET in pH=1, 3, 5, 7 buffer solutions at 55℃
Fig. 4-30 ID-VG curves of the Ta2O5 gate ISFET in pH=1, 3, 5, 7 buffer solutions at 65℃.
Fig. 4-31 Sensitivity of the Ta2O5 gate ISFET in pH=1, 3, 5, 7 buffer solutions at 65℃.
Fig. 4-32 ID-VG curves of the Ta2O5 gate ISFET in pH=1, 3, 5, 7 buffer solutions at 75℃.
Fig. 4-33 Sensitivity of the Ta2O5 gate ISFET in pH=1, 3, 5, 7 buffer solutions at 75℃.
Fig. 4-34 ID-VG curves of the Ta2O5 gate ISFET in pH=1, 3, 5, 7 buffer solutions at 85℃.
Fig. 4-35 Sensitivity of the Ta2O5 gate ISFET in pH=1, 3, 5, 7 buffer solutions at 85℃.
Fig. 4-36 Temperature sensitivity and correlation coefficient dependency of the Ta2O5 gate ISFET.
Fig. 4-37 Normalize the temperature sensitivity curve of the Ta2O5 gate ISFET.
Fig. 4-38 ID-VG curves of the Ta2O5 gate ISFET in pH=1 buffer solution at temperatures of 25℃, 35℃, 45℃, 55℃, 65℃, 75℃, and 85℃.
Fig. 4-39 ID-VG curves of the Ta2O5 gate ISFET in pH=3 buffer solution at temperatures of 25℃, 35℃, 45℃, 55℃, 65℃, 75℃, and 85℃.
Fig. 4-40 ID-VG curves of the Ta2O5 gate ISFET in pH=5 buffer solution at temperatures of 25℃, 35℃, 45℃, 55℃, 65℃, 75℃, and 85℃.
Fig. 4-41 ID-VG curves of the Ta2O5 gate ISFET in pH=7 buffer solution at temperatures of 25℃, 35℃, 45℃, 55℃, 65℃, 75℃, and 85℃.
Fig. 4-42 Iso-thermal point range of the Ta2O5 gate ISFET in pH=1, 3, 5, 7 buffer solutions.
Fig. 4-43 ID-VG curves of the Thermal Oxide gate ISFET in pH=1, 3, 5, 7 buffer solutions at 25℃.
Fig. 4-44 Sensitivity of the Thermal Oxide gate ISFET in pH=1, 3, 5, 7 buffer solutions at 25℃.
Fig. 4-45 ID-VG curves of the Thermal Oxide gate ISFET in pH=1, 3, 5, 7 buffer solutions at 35℃.
Fig. 4-46 Sensitivity of the Thermal Oxide gate ISFET in pH=1, 3, 5, 7 buffer solutions at 35℃.
Fig. 4-47 ID-VG curves of the Thermal Oxide gate ISFET in pH=1, 3, 5, 7 buffer solutions at 45℃.
Fig. 4-48 Sensitivity of the Thermal Oxide gate ISFET in pH=1, 3, 5, 7 buffer solutions at 45℃.
Fig. 4-49 ID-VG curves of the Thermal Oxide gate ISFET in pH=1, 3, 5, 7 buffer solutions at 55℃.
Fig. 4-50 Sensitivity of the Thermal Oxide gate ISFET in pH=1, 3, 5, 7 buffer solutions at 55℃.
Fig. 4-51 ID-VG curves of the Thermal Oxide gate ISFET in pH=1, 3, 5, 7 buffer solutions at 65℃.
Fig. 4-52 Sensitivity of the Thermal Oxide gate ISFET in pH=1, 3, 5, 7 buffer solutions at 65℃.
Fig. 4-53 ID-VG curves of the Thermal Oxide gate ISFET in pH=1, 3, 5, 7 buffer solutions at 75℃.
Fig. 4-54 Sensitivity of the Thermal Oxide gate ISFET in pH=1, 3, 5, 7 buffer solutions at 75℃.
Fig. 4-55 ID-VG curves of the Thermal Oxide gate ISFET in pH=1, 3, 5, 7 buffer solutions at 85℃.
Fig. 4-56 Sensitivity of the Thermal Oxide gate ISFET in pH=1, 3, 5, 7 buffer solutions at 85℃.
Fig. 4-57 Temperature sensitivity and correlation coefficient dependency of the Thermal Oxide gate ISFET.
Fig. 4-58 Normalize the temperature sensitivity curve of the Thermal Oxide gate ISFET.
Fig. 4-59 ID-VG curves of the Thermal Oxide gate ISFET in pH=1 buffer solution at temperatures of 25℃, 35℃, 45℃, 55℃, 65℃, 75℃, and 85℃.
Fig. 4-60 ID-VG curves of the Thermal Oxide gate ISFET in pH=3 buffer solution at temperatures of 25℃, 35℃, 45℃, 55℃, 65℃, 75℃, and 85℃.
Fig. 4-61 ID-VG curves of the Thermal Oxide gate ISFET in pH=5 buffer solution at temperatures of 25℃, 35℃, 45℃, 55℃, 65℃, 75℃, and 85℃
Fig. 4-62 ID-VG curves of the Thermal Oxide gate ISFET in pH=7 buffer solution at temperatures of 25℃, 35℃, 45℃, 55℃, 65℃, 75℃, and 85℃
Fig. 4-63 Iso-thermal point range of the Thermal Oxide gate ISFET in pH=1, 3, 5, 7 buffer solutions.
Fig. 4-64 ID-VG curves of the PE Oxide gate ISFET in pH=1, 3, 5, 7 buffer solutions at 25℃.
Fig. 4-65 Sensitivity of the PE Oxide gate ISFET in pH=1, 3, 5, 7 buffer solutions at 25℃.
Fig. 4-66 ID-VG curves of the PE Oxide gate ISFET in pH=1, 3, 5, 7 buffer solutions at 35℃.
Fig. 4-67 Sensitivity of the PE Oxide gate ISFET in pH=1, 3, 5, 7 buffer solutions at 35℃.
Fig. 4-68 ID-VG curves of the PE Oxide gate ISFET in pH=1, 3, 5, 7 buffer solutions at 45℃.
Fig. 4-69 Sensitivity of the PE Oxide gate ISFET in pH=1, 3, 5, 7 buffer solutions at 45℃.
Fig. 4-70 ID-VG curves of the PE Oxide gate ISFET in pH=1, 3, 5, 7 buffer solutions at 55℃.
Fig. 4-71 Sensitivity of the PE Oxide gate ISFET in pH=1, 3, 5, 7 buffer solutions at 55℃
Fig. 4-72 ID-VG curves of the PE Oxide gate ISFET in pH=1, 3, 5, 7 buffer solutions at 65℃.
Fig. 4-73 Sensitivity of the PE Oxide gate ISFET in pH=1, 3, 5, 7 buffer solutions at 65℃.
Fig. 4-74 ID-VG curves of the PE Oxide gate ISFET in pH=1, 3, 5, 7 buffer solutions at 75℃.
Fig. 4-75 Sensitivity of the PE Oxide gate ISFET in pH=1, 3, 5, 7 buffer solutions at 75℃.
Fig. 4-76 ID-VG curves of the PE Oxide gate ISFET in pH=1, 3, 5, 7 buffer solutions at 85℃.
Fig. 4-77 Sensitivity of the PE Oxide gate ISFET in pH=1, 3, 5, 7 buffer solutions at 85℃.
Fig. 4-78 Temperature sensitivity and correlation coefficient dependency of the PE Oxide gate ISFET.
Fig. 4-79 Normalize the temperature sensitivity curve of the PE Oxide gate ISFET.
Fig. 4-80 ID-VG curves of the PE Oxide gate ISFET in pH=1 buffer solution at temperatures of 25℃, 35℃, 45℃, 55℃, 65℃, 75℃, and 85℃.
Fig. 4-81 ID-VG curves of the PE Oxide gate ISFET in pH=3 buffer solution at temperatures of 25℃, 35℃, 45℃, 55℃, 65℃, 75℃, and 85℃.
Fig. 4-82 ID-VG curves of the PE Oxide gate ISFET in pH=5 buffer solution at temperatures of 25℃, 35℃, 45℃, 55℃, 65℃, 75℃, and 85℃.
Fig. 4-83 ID-VG curves of the PE Oxide gate ISFET in pH=7 buffer solution at temperatures of 25℃, 35℃, 45℃, 55℃, 65℃, 75℃, and 85℃.
Fig. 4-84 Iso-thermal point range of the PE Oxide gate ISFET in pH=1, 3, 5, 7 buffer solutions.
Fig. 4-85 The drift of ZrO2 gate ISFET with time.
Fig. 4-86 The relation of ZrO2 drift voltages and gate stress voltages.
Fig. 4-87 The drift of Ta2O5 gate ISFET with time.
Fig. 4-88 The relation of Ta2O5 drift voltages and gate stress voltages.
Fig. 4-89 The drift of Thermal Oxide gate ISFET with time.
Fig. 4-90 The relation of Thermal Oxide drift voltages and gate stress voltages.
Fig. 4-91 The drift of PE Oxide gate ISFET with time.
Fig. 4-92 The relation of PE Oxide drift voltages and gate stress voltages.
Fig. 4-93 VG vs Cycle time test of the ZrO2 gate ISFET in pH=7 buffer solution at either 25℃ or 85℃.
Fig. 4-94 △VG vs Cycle time test of the ZrO2 gate ISFET in pH=7 buffer solution at either 25℃ or 85℃.
Fig. 4-95 VG vs Cycle time test of the Ta2O5 gate ISFET in pH=7 buffer solution at either 25℃ or 85℃.
Fig. 4-96 △VG vs Cycle time test of the Ta2O5 gate ISFET in pH=7 buffer solution at either 25℃ or 85℃.
Fig. 4-97 VG vs Cycle time test of the Thermal Oxide gate ISFET in pH=7 buffer solution at either 25℃ or 85℃.
Fig. 4-98 △VG vs Cycle time test of the Thermal Oxide gate ISFET in pH=7 buffer solution at either 25℃ or 85℃
Fig. 4-99 VG vs Cycle time test of the PE Oxide gate ISFET in pH=7 buffer solution at either 25℃ or 85℃.
Fig. 4-100 △VG vs Cycle time test of the PE Oxide gate ISFET in pH=7 buffer solution at either 25℃ or 85℃.
Sensitivity (mV/pH)
3, 5, 7 buffer solutions at temperatures of 25℃, 35℃, 45℃, 55℃, 65℃, 75℃, and 85℃.
Sensitivity (%)
Table 4-2 Normalize the temperature sensitivity of the ZrO2,Thermal Oxide, Ta2O5, and PE Oxide gate ISFET in pH=1, 3, 5, 7 buffer solutions at temperatures of 25℃, 35℃, 45℃, 55℃, 65℃, 75℃, and 85℃.
Table 4-3 Temperature sensitivity correlation coefficient of the ZrO2,Thermal Oxide, Ta2O5, and PE Oxide gate ISFET in pH=1, 3, 5, 7 buffer solutions at temperatures of 25℃, 35℃, 45℃, 55℃, 65℃, 75℃, and 85℃.
Iso-thermal point VG
ISFET in pH=1, 3, 5, 7 buffer solutions.
VG STRESS= -1V
Table 4-5 The relation of the ZrO2,Ta2O5, Thermal Oxide, and PE Oxide drift voltages and gate stress voltages.
Cycle time=1
Table 4-6 VG vs Cycle time test of the ZrO2 gate ISFET in pH=7 buffer solution at either 25℃ or 85℃.
Table 4-8 VG vs Cycle time test of the Thermal Oxide gate ISFET in pH=7 buffer solution at either 25℃ or 85℃.
Cycle time=1
Table 4-9 VG vs Cycle time test of the PE Oxide gate ISFET in pH=7 buffer solution at either 25℃ or 85℃. ISFET in pH=7 buffer solution at either 25℃ or 85℃.
Cycle time
in pH=7 buffer solution at either 25℃ or 85℃.
Cycle time ISFET in pH=7 buffer solution.
Author biographical note 一、基本資料
姓名：黃明欽
生日：西元 1973/6/07 婚姻狀況：已婚
國別： 中華民國
電子信箱：mingchin@hldh.com
二、主要學歷
畢 業 學 校 國別 科系所或主修學門 學 位 起 迄 年 月
臺北市立內湖高工 中華民國 控制科 --- 1988/9-1991/6
私立華夏工業專科學校 中華民國 電機科 --- 1991/9-1993/6
國立雲林科技大學 中華民國 電機系 學士 1996/9-1998/6
國立交通大學 中華民國 電機與控制研究所 碩士 2003/9-2007/6
三、現職及相關之經歷
服務機關名稱 職稱 任職起迄期間
目前 致新科技股份有限公司 高級資深產品工程師 2002/8 ～至今
前一 國碁電子股份有限公司 研發工程師 1998/6 ～2002/8
前二 乾坤科技股份有限公司 助理工程師 1995/10 ～1996/3