Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
133 words
A photovoltaic cell comprising: a transparent substrate, a transparent first electrode layer on said substrate, a first semiconductor layer of a first conductivity type on said first electrode layer, said first semiconductor layer being approximately 25 to 300 Å in thickness and having activation energy of less than 0.3 eV for generation of major carriers, a second semiconductor layer of the first conductivity type on said first semiconductor layer, said second semiconductor layer being approximately 100 to 1000 Å in thickness and having activation energy of more than 0.3 eV for generation of major carriers, a third semiconductor layer of a second conductivity type on said second semiconductor layer, a fourth semiconductor layer of a third conductivity type on said third semiconductor layer, and a second electrode layer on said fourth semiconductor layer.
Claim 2
Dependent Claim
133 words
A photovoltaic cell comprising: a transparent substrate, a transparent first electrode layer on said substrate, a first semiconductor layer of a first conductivity type on said first electrode layer, said first semiconductor layer being approximately 25 to 300 Å in thickness and having activation energy of less than 0.3 eV for generation of major carriers, a second semiconductor layer of the first conductivity type on said first semiconductor layer, said second semiconductor layer being approximately 100 to 1000 Å in thickness and having activation energy of more than 0.3 eV for generation of major carriers, a third semiconductor layer of a second conductivity type on said second semiconductor layer, a fourth semiconductor layer of a third conductivity type on said third semiconductor layer, and a second electrode layer on said fourth semiconductor layer.
Claim 3
Dependent Claim
24 words
A photovoltaic cell as set forth in claim 1, wherein said first, second and third conductivity types are respectively P, I and N types.
Claim 4
Dependent Claim
22 words
A photovoltaic cell as set forth in claim 2, wherein said third semiconductor layer is made of amorphous silicon of I type.
Claim 5
Dependent Claim
47 words
A photovoltaic cell as set forth in claim 3, wherein said second semiconductor layer is an amorphous semiconductor having photoconductivity of more than 10 -5 Ω -1 cm -1 with irradiation of the optical spectrum (AM-1) on the equator with an intensity of 100 mW/cm 2 .
Claim 6
Dependent Claim
20 words
A photovoltaic cell as set forth in claim 4, wherein said first semiconductor layer comprises microcrystalline silicon of P type.
Claim 7
Dependent Claim
18 words
A photovoltaic cell as set forth in claim 5, wherein said microcrystalline silicon layer is formed by sputtering.
Claim 8
Dependent Claim
21 words
A photovoltaic cell as set forth in claim 3, wherein said first semiconductor layer is oxide of a platinum group metal.
Claim 9
Dependent Claim
15 words
A photovoltaic cell as set forth in claim 7, wherein said oxide is iridium oxide.
Claim 10
Dependent Claim
20 words
A photovoltaic cell as set forth in claim 8, wherein said second semiconductor layer is made of amorphous silicon carbide.
Claim 11
Dependent Claim
58 words
A photovoltaic cell as set forth in claim 9, wherein carbon content in said amorphous silicon carbide layer is decreased from the side adjacent to said first semiconductor layer to the side adjacent to said second semiconductor layer and the optical band gap of said amorphous silicon carbide layer decreases according to said decrease of the carbon content.
Claim 12
Dependent Claim
23 words
A photovoltaic cell as set forth in claim 1, wherein the thickness of said first semiconductor layer is preferably 30 to 200 Å.
Claim 13
Dependent Claim
24 words
A photovoltaic cell as set forth in claim 1, wherein the thickness of said first semiconductor layer is more preferably 40 to 150 Å.
Claim 14
Dependent Claim
23 words
A photovoltaic cell as set forth in claim 1, wherein the thickness of said second semiconductor layer is preferably 300 to 700 Å.
Claim 15
Dependent Claim
24 words
A photovoltaic cell as set forth in claim 1, wherein the thickness of said second semiconductor layer is more preferably 400 to 600 Å.
Claim 16
Dependent Claim
23 words
A photovoltaic cell as set forth in claim 1, wherein said first, second and third semiconductors are respectively N, I and P types.
Claim 17
Dependent Claim
19 words
A photovoltaic cell as set forth in claim 15, wherein said third semiconductor is amorphous silicon of I type.
Claim 18
Dependent Claim
20 words
A photovoltaic cell as set forth in claim 16, wherein said first semiconductor layer comprises microcrystalline silicon of N type.
Claim 19
Dependent Claim
18 words
A photovoltaic cell as set forth in claim 17, wherein said microcrystalline silicon layer is formed by sputtering.